Skip to content
Contents
ZIP Code Destiny

    Type to search. Planned chapters match by title only.

    Chapter 1.3 · The vanishing cradle

    Where births are falling

    Births in the counties that CDC WONDER identifies fell 4.6% from 2018 to 2024, by 5.6% in the least deprived quartile of counties and 7.3% in the most deprived, while births to mothers aged 15 to 29 fell and births to mothers aged 35 to 44 rose.

    Births in the 578578 countiesEstimandcount of countiesWeightsnone (full count)Populationcounties that WONDER natality identifies in every year from 2018 to 2024 and that have birthsPeriodbirths in 2018 to 2024SourceCDC WONDER natality counties that CDC WONDER identifies fell from 3.02 million3.02 million live birthsEstimandcount of live birthsWeightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018SourceCDC WONDER natality in 2018 to 2.88 million2.88 million live birthsEstimandcount of live birthsWeightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2024SourceCDC WONDER natality in 2024, a decline of 4.6%4.6% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2024Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018 to 2024SourceCDC WONDER natality. These counties have 100,000100,000 residentsEstimandpopulation size at which WONDER identifies a county, applied to an earlier population vintage than the 2020 census (a definition)Weightsnone (definition)Populationcounties that CDC WONDER natality identifiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality or more residents in the population vintage WONDER uses, and they record 79.4%79.4% percent of live births in the United StatesEstimandshare of births in the named countiesWeightsnone (full count)Populationlive births in the 50 states and DCPeriod2024SourceCDC WONDER natality of the births in the United States in 2024. In 380380 countiesEstimandcount of counties with fewer births in 2024 than in 2018Weightsnone (full count)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality of them births were lower in 2024 than in 2018, in 197197 countiesEstimandcount of counties with more births in 2024 than in 2018Weightsnone (full count)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality they were higher, and in oneone countiesEstimandcount of counties with the same number of births in 2018 and 2024Weightsnone (full count)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality the count was the same. From the 5th5th percentileEstimandpercentile used to describe the spread of county changes (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality to the 95th95th percentileEstimandpercentile used to describe the spread of county changes (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality percentile of counties, changes run from a decline of 16.5%16.5% percent of 2018 birthsEstimand5th percentile of the county changes in birthsn578 countiesWeightsnone (full count)Populationnamed counties at the 5th percentile of changePeriodbirths in 2018 and 2024SourceCDC WONDER natality to a gain of 19.9%19.9% percent of 2018 birthsEstimand95th percentile of the county changes in birthsn578 countiesWeightsnone (full count)Populationnamed counties at the 95th percentile of changePeriodbirths in 2018 and 2024SourceCDC WONDER natality, and the extremes (Figure 3) are a decline of 23.9%23.9% percent of 2018 birthsEstimandfall in the county's count of births from 2018 to 2024n4,127 birthsWeightsnone (full count)Populationthe named county with the largest decline (St. Louis city, MO)Periodbirths in 2018 and 2024SourceCDC WONDER natality in St. Louis city, Missouri, and a gain of 67.6%67.6% percent of 2018 birthsEstimandrise in the county's count of births from 2018 to 2024n1,786 birthsWeightsnone (full count)Populationthe named county with the largest gain (Kaufman County, TX)Periodbirths in 2018 and 2024SourceCDC WONDER natality in Kaufman County, Texas.

    Pooled over counties, births changed by 0.0% (95% CI −1.7% to 1.8%)0.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −1.7% to 1.8%n232 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census South regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the South, −8.4% (95% CI −10.4% to −6.3%)−8.4% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −10.4% to −6.3%n137 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census Midwest regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the Midwest, −7.9% (95% CI −10.7% to −5.0%)−7.9% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −10.7% to −5.0%n99 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census West regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the West and −5.0% (95% CI −7.3% to −2.5%)−5.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −7.3% to −2.5%n110 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census Northeast regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the Northeast. Pooled births fell by 5.6% (95% CI 2.8% to 8.2%)5.6% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 2.8% to 8.2%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the least deprived quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the least deprived quartile of these counties, by 2.6%2.6% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −0.6% to 5.3%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the second quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality and 3.1%3.1% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 1.6% to 4.5%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the third quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the second and third quartiles, and by 7.3% (95% CI 5.8% to 8.8%)7.3% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 5.8% to 8.8%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the most deprived quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the most deprived. The losses do not rise in steps with deprivation, and region and deprivation overlap, so the chapter looks at them together. The ages of mothers shifted too. Between 2018 and 2024 births fell by 24.6%24.6% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 22.7% to 26.5%n577 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 19 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 15 to 1915 to 19 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and rose by 19.5%19.5% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 17.0% to 22.3%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 40 to 44 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 40 to 4440 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, and the counties that lost the most births lost them among mothers under 3535 years of ageEstimandage below which a mother belongs to the younger groups in this chapter (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality.

    Everything in this chapter is a count of births in a county or a share of those births. A birth rate divides births by the women who could have had them, and the files behind this book have no county counts of women by age, so the chapter reports counts and shares and no rates. The babies in these counties are the subject of Chapter 1.1, Birthweight and preterm birth, which asks how heavy they were at birth, and of Chapter 1.2, Infant mortality, which follows them through the first year.

    Births have not returned to their 2018 level

    Births in the named counties fell from 2018 to 2020, rose through 2022, fell again to a low in 2023, when they were 5.5%5.5% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2023Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018 to 2023SourceCDC WONDER natality below 2018, and rose 0.9%0.9% percent of 2023 birthsEstimandrise in the count of births from 2023 to 2024Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2023 to 2024SourceCDC WONDER natality in 2024 (Figure 1). In 2020 they were 4.8%4.8% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2020Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018 to 2020SourceCDC WONDER natality below 2018, and by 2024 they were still 4.6%4.6% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2024Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018 to 2024SourceCDC WONDER natality below. WONDER pools the births of every smaller county in a state into one row, 4949 statesEstimandcount of pooled rowsWeightsnone (full count)Populationstates with counties below the threshold, each with one pooled Unidentified Counties rowPeriodbirths in 2018 to 2024SourceCDC WONDER natality rows in all. Those rows record 0.77 million0.77 million live birthsEstimandcount of live births in the pooled rowsWeightsnone (full count)Populationlive births in the counties that WONDER natality does not name, which it pools within each statePeriod2018SourceCDC WONDER natality births in 2018 and 0.75 million0.75 million live birthsEstimandcount of live births in the pooled rowsWeightsnone (full count)Populationlive births in the counties that WONDER natality does not name, which it pools within each statePeriod2024SourceCDC WONDER natality in 2024, a decline of 3.0%3.0% percent of 2018 birthsEstimandfall in the count of births in the pooled rows from 2018 to 2024Weightsnone (full count)Populationlive births in the counties that WONDER natality does not name, which it pools within each statePeriod2018 to 2024SourceCDC WONDER natality, so the named counties lost a larger share of their births than the rest of the country combined. Across the whole country births fell from 3.79 million3.79 million live birthsEstimandcount of live birthsWeightsnone (full count)Populationlive births in the 50 states and DCPeriod2018SourceCDC WONDER natality to 3.63 million3.63 million live birthsEstimandcount of live birthsWeightsnone (full count)Populationlive births in the 50 states and DCPeriod2024SourceCDC WONDER natality, a decline of 4.3%4.3% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2024Weightsnone (full count)Populationlive births in the 50 states and DCPeriod2018 to 2024SourceCDC WONDER natality. The count for 2024 is the one in the final report of the National Center for Health Statistics, and 2024 is final in these data.[1]

    Birth rates in the United States have been falling since the Great Recession. Kearney, Levine and Pardue document that birth rates fell between 2007 and 2020 across many groups of women, and they find that the recession explains only part of the early decline.[2] This chapter starts in 2018 and describes where the recent loss fell.

    Figure 1

    Births in the named counties fell 4.6% from 2018 to 2024 with a low in 2023, a larger fall than the 3.0% in all other counties

    Live births by year in the 578 counties that CDC WONDER identifies (counties with 100,000 or more residents in WONDER's population vintage) and in all other counties, which WONDER pools by state, 2018 to 2024, indexed to 2018 or as counts

    Show data
    Data for Births in the named counties fell 4.6% from 2018 to 2024 with a low in 2023, a larger fall than the 3.0% in all other counties
    measurenseriesvalueyear
    index3,020,813Named counties1002018
    births3,020,813Named counties30208132018
    index2,985,056Named counties98.822019
    births2,985,056Named counties29850562019
    index2,875,172Named counties95.182020
    births2,875,172Named counties28751722020
    index2,912,953Named counties96.432021
    births2,912,953Named counties29129532021
    index2,920,239Named counties96.672022
    births2,920,239Named counties29202392022
    index2,855,036Named counties94.512023
    births2,855,036Named counties28550362023
    index2,881,385Named counties95.382024
    births2,881,385Named counties28813852024
    index770,899Other counties1002018
    births770,899Other counties7708992018
    index762,484Other counties98.912019
    births762,484Other counties7624842019
    index738,475Other counties95.792020
    births738,475Other counties7384752020
    index751,339Other counties97.462021
    births751,339Other counties7513392021
    index747,519Other counties96.972022
    births747,519Other counties7475192022
    index740,981Other counties96.122023
    births740,981Other counties7409812023
    index747,549Other counties96.972024
    births747,549Other counties7475492024
    Births in the named counties drop to 2020, recover a little through 2022, reach a low in 2023 and rise in 2024. Births in the other counties are lowest in 2020 and end nearer their 2018 level. The index divides each year's births by the 2018 births of the same group of counties; the second view shows the counts.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: Births are full counts from birth certificates, so no interval is drawn. A count of births is not a birth rate: the series blends births per woman with the number of women.Source: CDC WONDER natality, births in 2018-2024; full counts of births (no sampling error)

    The 578578 countiesEstimandcount of countiesWeightsnone (full count)Populationcounties that WONDER natality identifies in every year from 2018 to 2024 and that have birthsPeriodbirths in 2018 to 2024SourceCDC WONDER natality named counties are the counties that WONDER identifies in every year from 2018 to 2024 and that have births in every year. WONDER lists twotwo countiesEstimandcount of listed counties whose births WONDER folded into the state's pooled rowWeightsnone (full count)Populationcounty identifiers that WONDER lists in every year from 2018 to 2024 but with no births (Cape May County NJ, Portsmouth city VA)Periodbirths in 2018 to 2024SourceCDC WONDER natality more county identifiers in every year, Cape May County, New Jersey, and Portsmouth city, Virginia, but gives them no births because it folded them into their state's pooled row, so they are left out. Every named county appears in every year from 2018 to 2024, so no county drops out of the panel by entering or leaving WONDER's list. The selection is by size as WONDER measured it. WONDER applies its threshold of 100,000100,000 residentsEstimandpopulation size at which WONDER identifies a county, applied to an earlier population vintage than the 2020 census (a definition)Weightsnone (definition)Populationcounties that CDC WONDER natality identifiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality residents to an earlier population estimate than the 2020 Census. By 2020 Census population, 2727 countiesEstimandcount of unnamed counties with a 2020 Census population of at least the thresholdn3,135 countiesWeightsnone (full count)Populationcounties outside Connecticut that WONDER pools although their 2020 Census population is 100,000 or morePeriod2020 CensusSourceCDC WONDER natality counties outside Connecticut that have 100,000100,000 residentsEstimandpopulation size at which WONDER identifies a county, applied to an earlier population vintage than the 2020 census (a definition)Weightsnone (definition)Populationcounties that CDC WONDER natality identifiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality or more residents are still in the pooled rows, among them Sumter County, Florida, Gallatin County, Montana, and Flagler County, Florida, and oneone countiesEstimandcount of named counties with a 2020 Census population below the thresholdn3,135 countiesWeightsnone (full count)Populationnamed counties outside Connecticut whose 2020 Census population is below the thresholdPeriod2020 CensusSourceCDC WONDER natality named county, Ashtabula County, Ohio, is below the line. The staged atlas has no 2020 count for Connecticut, whose counties are all named. Counties that grew past the line after WONDER's estimate therefore sit in the pooled rows, so the comparison of the 3.0%3.0% percent of 2018 birthsEstimandfall in the count of births in the pooled rows from 2018 to 2024Weightsnone (full count)Populationlive births in the counties that WONDER natality does not name, which it pools within each statePeriod2018 to 2024SourceCDC WONDER natality decline there with the 4.6%4.6% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2024Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018 to 2024SourceCDC WONDER natality decline in the named counties compares two groups defined by an earlier population estimate and not by size today. The named counties record 79.7%79.7% percent of live births in the United StatesEstimandshare of births in the named countiesWeightsnone (full count)Populationlive births in the 50 states and DCPeriod2018SourceCDC WONDER natality of births in 2018 and 79.4%79.4% percent of live births in the United StatesEstimandshare of births in the named countiesWeightsnone (full count)Populationlive births in the 50 states and DCPeriod2024SourceCDC WONDER natality in 2024, and the smallest of them recorded at least 613613 live birthsEstimandsmallest annual count of births in any of the named countiesn4,046 county-yearsWeightsnone (full count)Populationthe named county-year with the fewest birthsPeriodbirths in 2018 to 2024SourceCDC WONDER natality births in every year. County results in this chapter describe these counties and not the country. The pooled rows lost fewer births, with the caveat that they include counties that now exceed the line.

    Births held up in the South and fell elsewhere

    The Census Bureau groups states into the Northeast, the Midwest, the South and the West. The South, which has 1616 statesEstimandstates in the Census South region, besides the District of Columbia (a definition)Weightsnone (definition)PopulationstatesPeriodall years (a definition)SourceCDC WONDER natality states and the District of Columbia, holds 232232 countiesEstimandcount of countiesWeightsnone (full count)Populationnamed counties in the Census South region (16 states and DC)Periodbirths in 2018 to 2024SourceCDC WONDER natality of the named counties, or 40.1%40.1% percent of named countiesEstimandshare of named counties in the Census South region (16 states and DC)n578 countiesWeightsnone (full count)Populationnamed countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality. Pooled over its counties, the South's births changed by 0.0% (95% CI −1.7% to 1.8%)0.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −1.7% to 1.8%n232 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census South regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality from 2018 to 2024, an interval that includes zero. Births in the Midwest changed by −8.4% (95% CI −10.4% to −6.3%)−8.4% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −10.4% to −6.3%n137 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census Midwest regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality, in the West by −7.9% (95% CI −10.7% to −5.0%)−7.9% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −10.7% to −5.0%n99 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census West regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality and in the Northeast by −5.0% (95% CI −7.3% to −2.5%)−5.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −7.3% to −2.5%n110 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census Northeast regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality, so the intervals for those three regions lie below zero. The South's change is higher than the Northeast's by 5.0 percentage points (95% CI 2.0 percentage points to 7.9 percentage points)5.0 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 2.0 percentage points to 7.9 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, South minus NortheastPeriodbirths in 2018 and 2024SourceCDC WONDER natality, than the Midwest's by 8.4 percentage points (95% CI 5.7 percentage points to 11.1 percentage points)8.4 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 5.7 percentage points to 11.1 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, South minus MidwestPeriodbirths in 2018 and 2024SourceCDC WONDER natality and than the West's by 7.9 percentage points (95% CI 4.3 percentage points to 11.3 percentage points)7.9 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 4.3 percentage points to 11.3 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, South minus WestPeriodbirths in 2018 and 2024SourceCDC WONDER natality. The intervals come from a bootstrapBootstrap intervalA range for an estimate found by recomputing it on many random resamples of the data and reading the range from the results. It shows how much the estimate would vary from sample to sample. that resamples whole counties, so they show how much a region's pooled change depends on which counties it holds.

    Figure 2

    Of the 58 counties with the largest gains in births, 43 are in the South, which holds 40.1% of the named counties

    Percent change in live births from 2018 to 2024 by county, for the 578 counties that CDC WONDER identifies (counties with 100,000 or more residents in WONDER's population vintage)

    Loading county values

    Change in live births, 2018 to 2024 (%; the key ends at 20 either way)

    Fewer birthsMore births

    Values outside −20.0 to +20.0 take the end colors.

    No data (3,143 counties)

    Select a class to show only those places.

    Hover or tap a county for its value, or search by name. Zoom with the buttons on the map, then drag to move it.

    Counties toward the high end of the key gained births and counties toward the low end lost them. Gray hatched counties are not named by WONDER, which pools their births by state, so they have no value; the tooltip says so. Texas and Florida each hold 12 of the 58 counties in the top tenth by change, and no other state holds more than 5. Counties in the Midwest, the Northeast and the West more often lost births than gained them. The key ends at 20 percent in each direction, and 34 counties changed by more and are drawn at its end color.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: Births are full counts, so no interval is drawn for a county. A small county's count moves more from year to year by chance, so the shading of a county with few births is less stable than the shading of a large one.Note: The tooltip gives the value of a county whose change is beyond the end of the key.Note: Connecticut is shown as its eight legacy counties, the coding of the source. Alaska is drawn. Puerto Rico is not in these data and is not drawn.Source: CDC WONDER natality, births in 2018-2024; full counts of births (no sampling error); county changes are not weighted

    The map (Figure 2) shows the same split county by county. The top tenth of counties by change, with gains of 10.2%10.2% percent of 2018 birthsEstimandgain at the 90th percentile of the county changes in birthsn578 countiesWeightsnone (full count)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality or more, holds 5858 countiesEstimandcount of counties at or above the 90th percentile of changeWeightsnone (full count)Populationnamed counties in the top tenth of change in birthsPeriodbirths in 2018 and 2024SourceCDC WONDER natality counties, and 4343 countiesEstimandcount of those counties in the Census South region (16 states and DC)Weightsnone (full count)Populationnamed counties in the top tenth of change that are in the Census South regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality of them are in the South. The bottom tenth, with declines of 13.6%13.6% percent of 2018 birthsEstimandfall at the 10th percentile of the county changes in birthsn578 countiesWeightsnone (full count)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality or more, holds 5858 countiesEstimandcount of counties at or below the 10th percentile of changeWeightsnone (full count)Populationnamed counties in the bottom tenth of change in birthsPeriodbirths in 2018 and 2024SourceCDC WONDER natality counties, and 1313 countiesEstimandcount of those counties in the Census South region (16 states and DC)Weightsnone (full count)Populationnamed counties in the bottom tenth of change that are in the Census South regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality are in the South. Counted one county at a time, 65.7%65.7% percent of named countiesEstimandshare of counties with fewer births in 2024 than in 2018n578 countiesWeightsnone (full count)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality of the named counties lost births. The median county lost 3.8%3.8% percent of 2018 birthsEstimandmedian of the county changes in births, one county one countn578 countiesWeightsnone (full count)Populationthe median named countyPeriodbirths in 2018 and 2024SourceCDC WONDER natality, and from the 5th5th percentileEstimandpercentile used to describe the spread of county changes (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality to the 95th95th percentileEstimandpercentile used to describe the spread of county changes (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality percentile of counties, changes run from a decline of 16.5%16.5% percent of 2018 birthsEstimand5th percentile of the county changes in birthsn578 countiesWeightsnone (full count)Populationnamed counties at the 5th percentile of changePeriodbirths in 2018 and 2024SourceCDC WONDER natality to a gain of 19.9%19.9% percent of 2018 birthsEstimand95th percentile of the county changes in birthsn578 countiesWeightsnone (full count)Populationnamed counties at the 95th percentile of changePeriodbirths in 2018 and 2024SourceCDC WONDER natality. The pooled decline of 4.6%4.6% percent of 2018 birthsEstimandfall in the count of births from 2018 to 2024Weightsnone (full count)Populationlive births in the counties that CDC WONDER natality identifies in every year (counties with 100,000 or more residents in the population vintage WONDER uses)Period2018 to 2024SourceCDC WONDER natality is larger than the median county's because the pooled figure weights each county by its births and the median counts each county once.

    Figure 3

    The ten largest gains in births are all in the South, and the ten largest declines are spread across every Census region

    Percent change in live births from 2018 to 2024 for the ten named counties with the largest gains and the ten with the largest declines, of the 578 named counties

    • Largest gains
    • Largest declines
    Show data
    Data for The ten largest gains in births are all in the South, and the ten largest declines are spread across every Census region
    births_2018births_2024changecountygroup
    1786299367.58Kaufman County, TXLargest gains
    1526220344.36Comal County, TXLargest gains
    2572367042.69Hays County, TXLargest gains
    6650932540.23Williamson County, TXLargest gains
    1537209636.37Parker County, TXLargest gains
    987132033.74Brunswick County, NCLargest gains
    2214291431.62Ellis County, TXLargest gains
    2299297529.40Johnston County, NCLargest gains
    1173150127.96Bartow County, GALargest gains
    7355922025.36Montgomery County, TXLargest gains
    41273142−23.87St. Louis city, MOLargest declines
    30412361−22.36Hinds County, MSLargest declines
    13641062−22.14Humboldt County, CALargest declines
    31092449−21.23St. Clair County, ILLargest declines
    15181204−20.69Monroe County, PALargest declines
    15061195−20.65Terrebonne Parish, LALargest declines
    86976930−20.32San Francisco County, CALargest declines
    13261072−19.16Fayette County, PALargest declines
    46563769−19.05Orleans Parish, LALargest declines
    12461010−18.94Monroe County, INLargest declines
    Dots right of the zero line gained births and dots left of it lost them. The lead gain, in Kaufman County, Texas, is 67.6%, and the lead decline, in St. Louis city, Missouri, is 23.9%. Every county listed had at least 987 births in 2018, and small counts move more from year to year, so the order within each group is less stable than the groups.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: Births are full counts, so no interval is drawn. The data table lists each county's births in 2018 and 2024.Source: CDC WONDER natality, births in 2018-2024; full counts of births (no sampling error); county changes are not weighted

    Figure 3 lists the tenten countiesEstimandnumber of counties listed in each group of largest gains and largest declines (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality counties with the largest gains and the tenten countiesEstimandnumber of counties listed in each group of largest gains and largest declines (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality with the largest declines. All of the gains are in the South, in Texas, North Carolina and Georgia. The declines are spread across every region and include St. Louis city, Missouri, Hinds County, Mississippi, Humboldt County, California, San Francisco County and Orleans Parish, Louisiana. Every county listed had at least 987987 live birthsEstimandsmallest 2018 count of births among those countiesn20 countiesWeightsnone (full count)Populationthe 20 counties in the figure of largest gains and declinesPeriod2018SourceCDC WONDER natality births in 2018. Small counts move more from year to year by chance, so the order within each group is less stable than the groups themselves.

    A county's births change when women have fewer children, when the number of women of childbearing age changes, or both, and these data cannot separate them. WONDER places a birth in the mother's county of residence, so a county that adds young families counts their births, and a gain in a fast-growing county may reflect arrivals as much as larger families.

    The most deprived counties lost more births than the middle quartiles

    To place counties on a deprivation scale, each census tract carries its Area Deprivation IndexArea Deprivation Index (ADI)A score that ranks neighborhoods by income, education, employment and housing conditions drawn from the American Community Survey. In this book a higher national percentile means a more deprived neighborhood. national rank, which orders neighborhoods by income, education, employment and housing measures from the American Community Survey, with a higher rank meaning more deprived.[3] A tract's rank is the unweighted mean of the ranks of its block groups, and a county's rank is the average of its tracts' ranks, weighted by tract populationPopulation-weightedAveraged so that each place counts in proportion to its number of residents, which lets a large county move the result more than a small one. An unweighted average counts every place equally., the measure used in Chapter 1.1, Birthweight and preterm birth. Quartiles hold equal numbers of the named counties, so the most deprived quartile is relative to large counties and not to the nation.

    By 2024 pooled births in the most deprived quartile were 7.3% (95% CI 5.8% to 8.8%)7.3% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 5.8% to 8.8%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the most deprived quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality below 2018 (Figure 4). All four quartiles fell to 2020. In 2021 births in the other three quartiles rose and births in the most deprived quartile did not: its pooled change was −0.3% (95% CI −0.8% to 0.1%)−0.3% percent of 2020 birthsEstimandpooled change in the count of births from 2020 to 2021, bootstrap interval over countiesInterval95% CI −0.8% to 0.1%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the most deprived quartile of the named counties by county Area Deprivation Index rankPeriod2020 to 2021SourceCDC WONDER natality, an interval that includes zero, and the other quartiles rose by more, by 1.9 percentage points (95% CI 1.0 percentage points to 3.0 percentage points)1.9 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 1.0 percentage points to 3.0 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, change from 2020 to 2021 in the least deprived quartile minus the change in the most deprived quartilePeriod2020 to 2021SourceCDC WONDER natality in the least deprived quartile, 2.5 percentage points (95% CI 1.4 percentage points to 3.6 percentage points)2.5 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 1.4 percentage points to 3.6 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, change from 2020 to 2021 in the second quartile minus the change in the most deprived quartilePeriod2020 to 2021SourceCDC WONDER natality in the second and 1.3 percentage points (95% CI 0.5 percentage points to 2.2 percentage points)1.3 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 0.5 percentage points to 2.2 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, change from 2020 to 2021 in the third quartile minus the change in the most deprived quartilePeriod2020 to 2021SourceCDC WONDER natality in the third. The second and third quartiles lost 2.6% (95% CI −0.6% to 5.3%)2.6% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −0.6% to 5.3%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the second quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality and 3.1% (95% CI 1.6% to 4.5%)3.1% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 1.6% to 4.5%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the third quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality from 2018 to 2024, and the middle quartiles together lost 2.8% (95% CI 1.1% to 4.5%)2.8% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 1.1% to 4.5%n289 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the second and third quartiles together of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality, so the most deprived quartile lost 4.5 percentage points (95% CI 2.3 percentage points to 6.7 percentage points)4.5 percentage points percentage pointsEstimanddifference of two pooled falls in the count of births, shared bootstrap draws over countiesInterval95% CI 2.3 percentage points to 6.7 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, fall in births for the most deprived quartile minus the second and third quartiles togetherPeriodbirths in 2018 and 2024SourceCDC WONDER natality more than the middle quartiles. The least deprived quartile lost 5.6% (95% CI 2.8% to 8.2%)5.6% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 2.8% to 8.2%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the least deprived quartile of the named counties by county Area Deprivation Index rankPeriodbirths in 2018 and 2024SourceCDC WONDER natality. It lost 2.7 percentage points (95% CI −0.5 percentage points to 5.9 percentage points)2.7 percentage points percentage pointsEstimanddifference of two pooled falls in the count of births, shared bootstrap draws over countiesInterval95% CI −0.5 percentage points to 5.9 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, fall in births for the least deprived quartile minus the second and third quartiles togetherPeriodbirths in 2018 and 2024SourceCDC WONDER natality more than the middle quartiles and 1.7 percentage points (95% CI −1.2 percentage points to 5.0 percentage points)1.7 percentage points percentage pointsEstimanddifference of two pooled falls in the count of births, shared bootstrap draws over countiesInterval95% CI −1.2 percentage points to 5.0 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties, fall in births for the most deprived quartile minus the least deprived quartilePeriodbirths in 2018 and 2024SourceCDC WONDER natality less than the most deprived quartile, and both intervals include zero, so the data do not place it with either. A single slope does not summarize the pattern. Regressing each county's change on its deprivation rank gives +0.5 percentage points (95% CI −0.2 percentage points to 1.2 percentage points)+0.5 percentage points percentage points of change in births per ten points of county deprivation rankEstimandslope of the county change in births (percent) on county Area Deprivation Index rank, weighted by 2018 births, bootstrap interval over countiesInterval95% CI −0.2 percentage points to 1.2 percentage pointsn578 countiesWeights2018 birthsPopulationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality per ten ranks when counties are weighted by their births and −0.7 percentage points (95% CI −1.1 percentage points to −0.3 percentage points)−0.7 percentage points percentage points of change in births per ten points of county deprivation rankEstimandslope of the county change in births (percent) on county Area Deprivation Index rank, unweighted, one county one count, bootstrap interval over countiesInterval95% CI −1.1 percentage points to −0.3 percentage pointsn578 countiesWeightsnone (each county counts once)Populationnamed countiesPeriodbirths in 2018 and 2024SourceCDC WONDER natality when each county counts once, so the sign depends on the weights and only the unweighted interval excludes zero.

    Figure 4

    Births in 2024 were below 2018 in all four quartiles of counties, by 5.6% in the least deprived and 7.3% in the most deprived, and in 2021 the other three quartiles rose by more than the most deprived

    Pooled live births in each quartile of the 578 named counties by Area Deprivation Index rank, indexed to 2018 = 100, 2018 to 2024, with 95% intervals from a bootstrap over counties

    Show data
    Data for Births in 2024 were below 2018 in all four quartiles of counties, by 5.6% in the least deprived and 7.3% in the most deprived, and in 2021 the other three quartiles rose by more than the most deprived
    conf_highconf_lowindexnquartileyear
    n/an/a1001,224,834Least deprived quartile2018
    9998.1298.511,206,641Least deprived quartile2019
    95.5793.1094.281,154,721Least deprived quartile2020
    97.8493.8595.771,173,023Least deprived quartile2021
    97.7793.6095.591,170,851Least deprived quartile2022
    95.5790.7393.091,140,185Least deprived quartile2023
    97.1991.7794.431,156,626Least deprived quartile2024
    n/an/a100710,664Second quartile2018
    99.1897.9798.56700,447Second quartile2019
    96.5894.4095.43678,194Second quartile2020
    99.4695.6897.54693,209Second quartile2021
    100.995.9098.47699,762Second quartile2022
    99.1293.8196.40685,072Second quartile2023
    100.694.7097.44692,445Second quartile2024
    n/an/a100630,186Third quartile2018
    99.7598.9699.31625,862Third quartile2019
    96.7995.7296.20606,252Third quartile2020
    98.3596.2097.14612,146Third quartile2021
    98.9096.9397.88616,853Third quartile2022
    97.5995.0596.34607,127Third quartile2023
    98.4295.5296.86610,399Third quartile2024
    n/an/a100455,129Most deprived quartile2018
    99.7698.9099.34452,106Most deprived quartile2019
    96.2695.3595.80436,005Most deprived quartile2020
    96.1794.8095.48434,575Most deprived quartile2021
    96.1493.9995.09432,773Most deprived quartile2022
    94.0991.5992.86422,652Most deprived quartile2023
    94.2091.2392.70421,915Most deprived quartile2024
    Every line ends below the 2018 level. In 2021 the lines for the other three quartiles rise while the line for the most deprived quartile does not, and the differences between them and the most deprived quartile have intervals above zero. Each line is the pooled births of the counties in a quartile divided by the same counties' 2018 births. Bands show how much a quartile's pooled change depends on which counties it holds.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: A tract's Area Deprivation Index national rank (1 is least deprived, 100 most) is the unweighted mean of the ranks of its block groups. A county's deprivation rank is the mean of its tracts' ranks weighted by 2019-2023 tract population. Quartiles hold equal numbers of the named counties, so the most deprived quartile is relative to large counties and not to the nation. The index is a measure of neighborhoods, averaged to counties.Note: Intervals are 95% intervals from a bootstrap over counties (replicates and seed in the methods note). Births are full counts, so an interval shows how much a pooled figure depends on which counties are in the group, not sampling error in the counts. The 2018 point is the base and has no interval.Source: CDC WONDER natality, births in 2018-2024; full counts of births; counties grouped by Area Deprivation Index 2023 with ACS 2019-2023 tract population (population-weighted); pooled over counties by births (births-weighted); intervals from a bootstrap over counties

    Region and deprivation overlap. Of the counties in the most deprived quartile, 45%45% percent of countiesEstimandshare in the Census South region (16 states and DC)n145 countiesWeightsnone (full count)Populationcounties in the most deprived quartile of the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality are in the South, against 24%24% percent of countiesEstimandshare in the Census South region (16 states and DC)n144 countiesWeightsnone (full count)Populationcounties in the least deprived quartile of the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality of the counties in the least deprived quartile. Figure 5 splits the quartiles by region. The most deprived quartile lost births in every region: 9.3% (95% CI 6.6% to 11.8%)9.3% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 6.6% to 11.8%n22 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the most deprived quartile of the named counties in the Census Northeast regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the Northeast, 9.2% (95% CI 6.3% to 11.6%)9.2% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 6.3% to 11.6%n53 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the most deprived quartile of the named counties in the Census Midwest regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the Midwest, 5.0% (95% CI 2.9% to 7.0%)5.0% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 2.9% to 7.0%n65 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the most deprived quartile of the named counties in the Census South regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the South and 9.3%9.3% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024; no interval, because the cell holds fewer than 10 counties (all of them lost births)n5 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births in the most deprived quartile of the named counties in the Census West regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality in the West. The West's most deprived quartile holds only 55 countiesEstimandcount of countiesWeightsnone (full count)Populationcounties in the most deprived quartile of the named counties in the Census West regionPeriodbirths in 2018 to 2024SourceCDC WONDER natality counties, all of which lost births, and a bootstrap over so few counties is mechanical, so no interval is printed for it. In the South the other three quartiles together changed by +1.1% (95% CI −0.9% to 3.4%)+1.1% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −0.9% to 3.4%n167 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the three less deprived quartiles of the named counties in the Census South regionPeriodbirths in 2018 and 2024SourceCDC WONDER natality, which is higher than the change in the South's most deprived quartile by 6.1 percentage points (95% CI 3.2 percentage points to 9.0 percentage points)6.1 percentage points percentage pointsEstimanddifference of two pooled changes in the count of births, shared bootstrap draws over countiesInterval95% CI 3.2 percentage points to 9.0 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births in the named counties in the Census South region, three less deprived quartiles minus the most deprivedPeriodbirths in 2018 and 2024SourceCDC WONDER natality. The South's flat total therefore combines a loss in its most deprived counties with no clear change elsewhere.

    Figure 5

    The most deprived quartile of counties lost births in every Census region, and in the South the other three quartiles show no clear loss

    Pooled change in live births from 2018 to 2024 by Census region and quartile of county deprivation rank, named counties, with 95% intervals from a bootstrap over counties

    −12.0%0.0%+12.0%
    Faded: the interval includes 0.0%
    Heatmap of four Census regions by four deprivation quartiles, showing the pooled percent change in births from 2018 to 2024. Every cell in the most deprived column is negative. In the South row the three less deprived cells are near zero and faded, while cells for the West, Midwest and Northeast are mostly negative.
    RegionLeast deprived quartileSecond quartileThird quartileMost deprived quartile
    Northeast−4.4%, interval −7.7% to +0.1%, n = 39−2.0%, interval −3.7% to −0.1%, n = 25−7.7%, interval −9.9% to −4.4%, n = 24−9.3%, interval −11.8% to −6.6%, n = 22
    Midwest−5.7%, n = 9−10.6%, interval −14.1% to −4.3%, n = 26−6.1%, interval −7.5% to −4.8%, n = 49−9.2%, interval −11.6% to −6.3%, n = 53
    South+2.1%, interval −4.1% to +8.7%, n = 35+1.3%, interval −1.6% to +4.6%, n = 69+0.3%, interval −1.8% to +3.7%, n = 63−5.0%, interval −7.0% to −2.9%, n = 65
    West−8.4%, interval −11.6% to −4.7%, n = 61−4.5%, interval −8.0% to +1.8%, n = 25−9.3%, n = 8−9.3%, n = 5
    Show data
    Data for The most deprived quartile of counties lost births in every Census region, and in the South the other three quartiles show no clear loss
    births_2018changeconf_highconf_lown_lost_birthsn_unitsquartileregion
    338526−4.360.120−7.662439Least deprived quartileNortheast
    76401−1.99−0.060−3.671625Second quartileNortheast
    96145−7.73−4.41−9.892024Third quartileNortheast
    48096−9.26−6.59−11.842122Most deprived quartileNortheast
    52620−5.68n/an/a69Least deprived quartileMidwest
    158400−10.63−4.34−14.081926Second quartileMidwest
    156974−6.13−4.79−7.504649Third quartileMidwest
    189123−9.20−6.26−11.604453Most deprived quartileMidwest
    1839032.158.71−4.061735Least deprived quartileSouth
    3719251.304.59−1.592569Second quartileSouth
    3354040.3403.71−1.792363Third quartileSouth
    208110−5.02−2.92−6.954365Most deprived quartileSouth
    649785−8.37−4.74−11.554661Least deprived quartileWest
    103938−4.511.79−7.961725Second quartileWest
    41663−9.28n/an/a88Third quartileWest
    9800−9.27n/an/a55Most deprived quartileWest
    Cells toward the low end of the key lost births, and faded cells have an interval that includes zero. Cells with fewer than 10 counties show no interval. The cells in the most deprived column that show an interval lie below zero, and in the South row the three less deprived cells are faded. The tooltip gives the number of counties in each cell and the data table the number that lost births.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: A tract's Area Deprivation Index national rank (1 is least deprived, 100 most) is the unweighted mean of the ranks of its block groups. A county's deprivation rank is the mean of its tracts' ranks weighted by 2019-2023 tract population. Quartiles hold equal numbers of the named counties, so the most deprived quartile is relative to large counties and not to the nation. The index is a measure of neighborhoods, averaged to counties.Note: Intervals are 95% intervals from a bootstrap over counties (replicates and seed in the methods note). Births are full counts, so an interval shows how much a pooled figure depends on which counties are in the group, not sampling error in the counts. A cell with fewer than 10 counties shows no interval; in the West, the most deprived and third quartiles hold few counties, and the least deprived quartile of the Midwest holds fewer than 10, so those cells are thin.Note: The Census South region is 16 states and DC; the Northeast, Midwest and West follow the Census Bureau's regions.Source: CDC WONDER natality, births in 2018-2024; full counts of births; counties grouped by Area Deprivation Index 2023 with ACS 2019-2023 tract population (population-weighted); pooled over counties by births (births-weighted); intervals from a bootstrap over counties

    These are patterns across counties and describe groups of births, not the mothers in any one county. The index measures neighborhoods averaged to counties, and it understates deprivation in high-cost cities, so some counties in the least deprived quartile hold neighborhoods that are more deprived than their rank suggests.

    A larger share of births were to older mothers in 2024

    WONDER splits each county's births by the mother's age in nine bands. Six of them, the bands from 15 to 1915 to 19 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality through 40 to 4440 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, are published for nearly every county and year. Of the 24,27624,276 cellsEstimandcount of cellsWeightsnone (full count)Populationcounty-year-by-age cells for mothers aged 15 to 44 in the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality county-year cells for those bands, WONDER withholdsSuppressionThe withholding of a number because the count behind it is too small to publish without risking the identification of a person. A suppressed value is missing, not zero. 1111 cellsEstimandcount of cells with 1 to 9 births, which WONDER withholdsWeightsnone (full count)Populationcounty-year-by-age cells for mothers aged 15 to 44 in the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality. Each holds fewer than 1010 birthsEstimanda cell with fewer births than this is withheld (a definition)Weightsnone (definition)Populationcells of the WONDER natality filesPeriodbirths in 2018 to 2024SourceCDC WONDER natality births, so together they hold at most 9999 live birthsEstimandlargest number of births the withheld cells could hold: 9 births in eachWeightsnone (full count)Populationwithheld cells for mothers aged 15 to 44Periodbirths in 2018 to 2024SourceCDC WONDER natality births, against 20.4 million20.4 million live birthsEstimandcount of births in published cellsn20,431,379 birthsWeightsnone (full count)Populationlive births in the published age-of-mother cells of the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality in published cells. The other three bands, mothers under 1515 years of ageEstimandage below which WONDER's under-15 band applies; mothers under this age are left out (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and mothers 4545 years of ageEstimandage at which WONDER's 45-to-49 band begins; mothers of this age and older are left out (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and over, are mostly withheld, with 6,5946,594 cellsEstimandcount of cells with 1 to 9 births, which WONDER withholdsWeightsnone (full count)Populationcounty-year-by-age cells for mothers under 15 and 45 and over in the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality of 12,13812,138 cellsEstimandcount of cellsWeightsnone (full count)Populationcounty-year-by-age cells for mothers under 15 and 45 and over in the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality cells missing. The published cells hold 0.26%0.26% percent of live birthsEstimandshare of those births to mothers under 15 or 45 and over, in published cellsWeightsnone (full count)Populationlive births in the published age-of-mother cells of the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality of births and the withheld ones at most 0.29%0.29% percent of live birthsEstimandlargest share of births the withheld tail cells could hold: 9 births in each, over births in published cellsWeightsnone (full count)Populationlive births in the published age-of-mother cells of the named countiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality, so the chapter leaves all three bands out and compares mothers aged 15 to 4415 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality. A withheld cell is missing, never zero, and nothing is recovered from county totals.

    From 2018 to 2024, births fell by 24.6% (95% CI 22.7% to 26.5%)24.6% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 22.7% to 26.5%n577 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 19 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 15 to 1915 to 19 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, by 16.6% (95% CI 15.0% to 18.3%)16.6% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 15.0% to 18.3%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 20 to 24 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 20 to 2420 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and by 11.2% (95% CI 9.6% to 12.9%)11.2% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 9.6% to 12.9%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 25 to 29 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 25 to 2925 to 29 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality. Births to mothers aged 30 to 3430 to 34 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality changed by +1.0% (95% CI −0.6% to 2.6%)+1.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI −0.6% to 2.6%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 30 to 34 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality, an interval that includes zero. Births rose by 9.2% (95% CI 7.3% to 11.0%)9.2% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 7.3% to 11.0%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 35 to 39 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 35 to 3935 to 39 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and by 19.5% (95% CI 17.0% to 22.3%)19.5% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024, bootstrap interval over countiesInterval95% CI 17.0% to 22.3%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 40 to 44 in the named counties that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 40 to 4440 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality (Figure 6). As shares of births to mothers aged 15 to 4415 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, mothers aged 15 to 2415 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality went from 21.8% (95% CI 21.0% to 22.7%)21.8% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 21.0% to 22.7%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 15 to 24Period2018SourceCDC WONDER natality to 18.7% (95% CI 18.0% to 19.5%)18.7% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 18.0% to 19.5%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 15 to 24Period2024SourceCDC WONDER natality, a fall of 3.1 percentage points (95% CI 2.9 percentage points to 3.3 percentage points)3.1 percentage points percentage pointsEstimandchange from 2018 to 2024 in the pooled share of births, shared bootstrap draws over countiesInterval95% CI 2.9 percentage points to 3.3 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 15 to 24Periodbirths in 2018 and 2024SourceCDC WONDER natality, and mothers aged 35 to 4435 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality went from 19.7% (95% CI 18.9% to 20.5%)19.7% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 18.9% to 20.5%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 35 to 44Period2018SourceCDC WONDER natality to 22.9% (95% CI 22.1% to 23.8%)22.9% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 22.1% to 23.8%n578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 35 to 44Period2024SourceCDC WONDER natality, a rise of 3.2 percentage points (95% CI 3.1 percentage points to 3.4 percentage points)3.2 percentage points percentage pointsEstimandchange from 2018 to 2024 in the pooled share of births, shared bootstrap draws over countiesInterval95% CI 3.1 percentage points to 3.4 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually, births in published cells; mothers aged 35 to 44Periodbirths in 2018 and 2024SourceCDC WONDER natality. The shift continues a rise in the mean age of mothers that the National Center for Health Statistics documented for every birth order from 2000 to 2014.[4]

    Figure 6

    Births fell for mothers aged 15 to 29, changed little for mothers aged 30 to 34 and rose for mothers aged 35 to 44 from 2018 to 2024

    Pooled change in live births by mother's age band, 2018 to 2024, in the 578 named counties, with 95% intervals from a bootstrap over counties

    Mother's age (years)

    Show data
    Data for Births fell for mothers aged 15 to 29, changed little for mothers aged 30 to 34 and rose for mothers aged 35 to 44 from 2018 to 2024
    agebirths_2018births_2024changeconf_highconf_lown_units
    15 to 1912975797772−24.65−22.72−26.53577
    20 to 24527582439765−16.65−14.98−18.31578
    25 to 29848726753795−11.19−9.57−12.87578
    30 to 349109779202821.022.65−0.620578
    35 to 394907055356309.1611.057.32578
    40 to 4410303012308519.4722.3417.02578
    Bars for the three youngest bands lie below zero and bars for the two oldest lie above it, so the bars climb with age. The bar for mothers aged 30 to 34 is near zero and its interval includes zero. Each bar compares a band's births in 2024 with its births in 2018, pooled over the counties that publish the band in both years.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: Intervals are 95% intervals from a bootstrap over counties (replicates and seed in the methods note). Births are full counts, so an interval shows how much a pooled figure depends on which counties are in the group, not sampling error in the counts.Note: WONDER splits births into nine age bands. Mothers under 15 and mothers 45 and over are left out because WONDER withholds most of those cells; the methods note gives the counts. A withheld cell is missing, never zero, and a county that withholds a band in 2018 or 2024 is left out of that band's bar; the data table gives the number of counties in each bar.Source: CDC WONDER natality, births in 2018-2024; full counts of births by mother's age; changes pooled over counties; intervals from a bootstrap over counties

    These are births and not birth rates. A fall in births to mothers aged 15 to 1915 to 19 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality can mean fewer births per teenager or fewer teenagers in the county, and the files behind this book have no county counts of women by age. A different measure of teen births, for women who grew up in each census tract, is in Chapter 3.4, Teen births.

    The age mix differs more across counties than it changed

    In 2018 the share of births to mothers aged 15 to 2415 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality was 17.0% (95% CI 15.6% to 18.3%)17.0% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 15.6% to 18.3%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 15 to 24Period2018SourceCDC WONDER natality in the least deprived quartile of counties and 30.9% (95% CI 29.9% to 32.1%)30.9% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 29.9% to 32.1%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 15 to 24Period2018SourceCDC WONDER natality in the most deprived, a gap of 14.0 percentage points (95% CI 12.3 percentage points to 15.8 percentage points)14.0 percentage points percentage pointsEstimanddifference of two pooled shares of births, shared bootstrap draws over countiesInterval95% CI 12.3 percentage points to 15.8 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; most deprived quartile minus least deprived quartilePeriod2018SourceCDC WONDER natality. In 2024 the shares were 14.5% (95% CI 13.4% to 15.5%)14.5% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 13.4% to 15.5%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 15 to 24Period2024SourceCDC WONDER natality and 26.9% (95% CI 25.8% to 28.0%)26.9% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 25.8% to 28.0%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 15 to 24Period2024SourceCDC WONDER natality, a gap of 12.4 percentage points (95% CI 11.0 percentage points to 14.0 percentage points)12.4 percentage points percentage pointsEstimanddifference of two pooled shares of births, shared bootstrap draws over countiesInterval95% CI 11.0 percentage points to 14.0 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; most deprived quartile minus least deprived quartilePeriod2024SourceCDC WONDER natality. For mothers aged 35 to 4435 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality the 2018 shares were 24.3% (95% CI 23.1% to 25.5%)24.3% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 23.1% to 25.5%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 35 to 44Period2018SourceCDC WONDER natality in the least deprived quartile and 13.0% (95% CI 12.5% to 13.5%)13.0% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 12.5% to 13.5%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 35 to 44Period2018SourceCDC WONDER natality in the most deprived, a gap of 11.3 percentage points (95% CI 10.0 percentage points to 12.5 percentage points)11.3 percentage points percentage pointsEstimanddifference of two pooled shares of births, shared bootstrap draws over countiesInterval95% CI 10.0 percentage points to 12.5 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; least deprived quartile minus most deprived quartilePeriod2018SourceCDC WONDER natality, and in 2024 they were 27.8% (95% CI 26.4% to 29.2%)27.8% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 26.4% to 29.2%n144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the least deprived quartile of counties by deprivation rank, mothers aged 35 to 44Period2024SourceCDC WONDER natality and 15.8% (95% CI 15.1% to 16.5%)15.8% percent of live births to mothers aged 15 to 44Estimandpooled share of births in published cells, bootstrap interval over countiesInterval95% CI 15.1% to 16.5%n145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually in the most deprived quartile of counties by deprivation rank, mothers aged 35 to 44Period2024SourceCDC WONDER natality, a gap of 12.0 percentage points (95% CI 10.5 percentage points to 13.5 percentage points)12.0 percentage points percentage pointsEstimanddifference of two pooled shares of births, shared bootstrap draws over countiesInterval95% CI 10.5 percentage points to 13.5 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; least deprived quartile minus most deprived quartilePeriod2024SourceCDC WONDER natality (Figure 7).

    Every quartile moved in the same direction. The share of births to mothers aged 15 to 2415 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality fell by 2.5 percentage points (95% CI 1.9 percentage points to 3.0 percentage points)2.5 percentage points percentage pointsEstimandchange from 2018 to 2024 in the pooled share of births, shared bootstrap draws over countiesInterval95% CI 1.9 percentage points to 3.0 percentage pointsn144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; least deprived quartilePeriodbirths in 2018 and 2024SourceCDC WONDER natality in the least deprived quartile and by 4.0 percentage points (95% CI 3.7 percentage points to 4.4 percentage points)4.0 percentage points percentage pointsEstimandchange from 2018 to 2024 in the pooled share of births, shared bootstrap draws over countiesInterval95% CI 3.7 percentage points to 4.4 percentage pointsn145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 15 to 24; most deprived quartilePeriodbirths in 2018 and 2024SourceCDC WONDER natality in the most deprived, and the share to mothers aged 35 to 4435 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality rose by 3.5 percentage points (95% CI 3.1 percentage points to 3.9 percentage points)3.5 percentage points percentage pointsEstimandchange from 2018 to 2024 in the pooled share of births, shared bootstrap draws over countiesInterval95% CI 3.1 percentage points to 3.9 percentage pointsn144 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; least deprived quartilePeriodbirths in 2018 and 2024SourceCDC WONDER natality and by 2.8 percentage points (95% CI 2.5 percentage points to 3.1 percentage points)2.8 percentage points percentage pointsEstimandchange from 2018 to 2024 in the pooled share of births, shared bootstrap draws over countiesInterval95% CI 2.5 percentage points to 3.1 percentage pointsn145 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individually; mothers aged 35 to 44; most deprived quartilePeriodbirths in 2018 and 2024SourceCDC WONDER natality. The share of young mothers fell by 1.5 percentage points (95% CI 0.9 percentage points to 2.2 percentage points)1.5 percentage points percentage pointsEstimanddifference of two changes in pooled shares: fall in the share of births to mothers aged 15 to 24, most deprived quartile minus least deprived quartile, shared bootstrap draws over countiesInterval95% CI 0.9 percentage points to 2.2 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individuallyPeriodbirths in 2018 and 2024SourceCDC WONDER natality more in the most deprived quartile, and the share of older mothers rose by 0.7 percentage points (95% CI 0.3 percentage points to 1.2 percentage points)0.7 percentage points percentage pointsEstimanddifference of two changes in pooled shares: rise in the share of births to mothers aged 35 to 44, least deprived quartile minus most deprived quartile, shared bootstrap draws over countiesInterval95% CI 0.3 percentage points to 1.2 percentage pointsn578 countiesWeightsbirths in each county (a pooled ratio of sums over counties); interval from a bootstrap over countiesPopulationlive births to mothers aged 15 to 44 in the counties that CDC WONDER natality names individuallyPeriodbirths in 2018 and 2024SourceCDC WONDER natality more in the least deprived quartile, so the shifts differ in size. Each is much smaller than the gap between quartiles.

    Figure 7

    In every quartile of county deprivation the share of births to older mothers rose and the share to younger mothers fell, and the differences between quartiles are larger than those changes

    Share of births to mothers aged 15 to 24 and to mothers aged 35 to 44, among births to mothers aged 15 to 44, by quartile of county deprivation rank, 2018 and 2024, with 95% intervals from a bootstrap over counties

    • 2018
    • 2024
    Show data
    Data for In every quartile of county deprivation the share of births to older mothers rose and the share to younger mothers fell, and the differences between quartiles are larger than those changes
    group_labelhi1hi2lo1lo2measuren_unitsy2018y2024
    All named counties22.6719.4820.9917.98Mothers aged 15 to 2457821.8318.73
    Least deprived quartile18.2715.5115.5713.42Mothers aged 15 to 2414416.9614.46
    Second quartile22.0918.7520.0716.95Mothers aged 15 to 2414521.0117.80
    Third quartile26.5523.1124.7221.20Mothers aged 15 to 2414425.6322.18
    Most deprived quartile32.0828.0329.9325.83Mothers aged 15 to 2414530.9426.91
    All named counties20.5123.8018.9222.08Mothers aged 35 to 4457819.7222.95
    Least deprived quartile25.4629.1823.0526.40Mothers aged 35 to 4414424.3227.84
    Second quartile20.4523.8618.5121.75Mothers aged 35 to 4414519.5322.86
    Third quartile16.4119.4015.1718.01Mothers aged 35 to 4414415.8718.76
    Most deprived quartile13.5016.5212.5015.07Mothers aged 35 to 4414513.0115.79
    In the first block the 2024 dot lies left of the 2018 dot in every row, and in the second block it lies right. Rows move steadily with deprivation, and the distance between the top and bottom quartile rows is wider than the distance any dot moved. Shares are pooled over counties and use births in published age cells.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: A tract's Area Deprivation Index national rank (1 is least deprived, 100 most) is the unweighted mean of the ranks of its block groups. A county's deprivation rank is the mean of its tracts' ranks weighted by 2019-2023 tract population. Quartiles hold equal numbers of the named counties, so the most deprived quartile is relative to large counties and not to the nation. The index is a measure of neighborhoods, averaged to counties.Note: Intervals are 95% intervals from a bootstrap over counties (replicates and seed in the methods note). Births are full counts, so an interval shows how much a pooled figure depends on which counties are in the group, not sampling error in the counts. Shares are of births to mothers aged 15 to 44; mothers under 15 and mothers 45 and over are left out, and withheld cells are missing.Source: CDC WONDER natality, births in 2018-2024; full counts of births by mother's age; counties grouped by Area Deprivation Index 2023 with ACS 2019-2023 tract population (population-weighted); pooled over counties by births (births-weighted); intervals from a bootstrap over counties

    Counties that lost the most births lost them among younger mothers

    Sorting counties by the change in their total births shows where in the age range the loss fell (Figure 8). The 144144 countiesEstimandcount of countiesWeightsnone (full count)Populationnamed counties in the quarter with the largest declines in birthsPeriodbirths in 2018 and 2024SourceCDC WONDER natality counties in the quarter with the largest declines, falls of 8.8%8.8% percent of 2018 birthsEstimandsmallest fall among the counties in the largest-decline quarter (the group's own boundary member)n144 countiesWeightsnone (full count)Populationthe quarter of named counties with the largest declinesPeriodbirths in 2018 and 2024SourceCDC WONDER natality or more, lost 13.5%13.5% percent of 2018 birthsEstimandfall in the pooled count of births from 2018 to 2024Weightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births in the quarter of named counties with the largest declinesPeriodbirths in 2018 and 2024SourceCDC WONDER natality of their births in all. Their births fell by 32.9%32.9% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 15 to 19 in the quarter of named counties with the largest declines that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 15 to 1915 to 19 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, by 25.1%25.1% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 20 to 24 in the quarter of named counties with the largest declines that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 20 to 2420 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, by 21.1%21.1% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 25 to 29 in the quarter of named counties with the largest declines that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 25 to 2925 to 29 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and by 8.8%8.8% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 30 to 34 in the quarter of named counties with the largest declines that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 30 to 3430 to 34 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality. Births to mothers aged 35 to 3935 to 39 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality changed by −0.1%−0.1% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 35 to 39 in the quarter of named counties with the largest declines that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality, and births to mothers aged 40 to 4440 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality rose by 9.6%9.6% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 40 to 44 in the quarter of named counties with the largest declines that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality. The 145145 countiesEstimandcount of countiesWeightsnone (full count)Populationnamed counties in the quarter with the largest gains in birthsPeriodbirths in 2018 and 2024SourceCDC WONDER natality counties in the quarter with the largest gains, gains of 2.6%2.6% percent of 2018 birthsEstimandsmallest gain among the counties in the largest-gain quarter (the group's own boundary member)n145 countiesWeightsnone (full count)Populationthe quarter of named counties with the largest gainsPeriodbirths in 2018 and 2024SourceCDC WONDER natality or more, added 11.2%11.2% percent of 2018 birthsEstimandrise in the pooled count of births from 2018 to 2024Weightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births in the quarter of named counties with the largest gainsPeriodbirths in 2018 and 2024SourceCDC WONDER natality in all. Births in those counties fell by 13.0%13.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n144 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 15 to 19 in the quarter of named counties with the largest gains that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 15 to 1915 to 19 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality and by 4.0%4.0% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n145 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 20 to 24 in the quarter of named counties with the largest gains that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 20 to 2420 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality, and rose in every older band, from 5.8%5.8% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n145 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 25 to 29 in the quarter of named counties with the largest gains that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 25 to 2925 to 29 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality to 39.3%39.3% percent of 2018 birthsEstimandpooled change in the count of births from 2018 to 2024n145 countiesWeightsbirths (a pooled ratio of totals over counties; full counts)Populationlive births to mothers aged 40 to 44 in the quarter of named counties with the largest gains that publish the band in both yearsPeriodbirths in 2018 and 2024SourceCDC WONDER natality among mothers aged 40 to 4440 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality.

    Figure 8

    Counties with the largest declines in births lost births at every age under 35, and counties with the largest gains added births at every age from 25

    Pooled change in live births from 2018 to 2024 by mother's age band, in four equal-sized groups of the 578 named counties formed by the change in their total births

    Show data
    Data for Counties with the largest declines in births lost births at every age under 35, and counties with the largest gains added births at every age from 25
    ageage_positionchangegroupn_units
    15 to 191−32.87Largest declines144
    20 to 242−25.09Largest declines144
    25 to 293−21.11Largest declines144
    30 to 344−8.77Largest declines144
    35 to 395−0.060Largest declines144
    40 to 4469.55Largest declines144
    15 to 191−25.21Smaller declines145
    20 to 242−17.85Smaller declines145
    25 to 293−13.39Smaller declines145
    30 to 344−0.670Smaller declines145
    35 to 3959.07Smaller declines145
    40 to 44620.34Smaller declines145
    15 to 191−20.90Little change144
    20 to 242−12.76Little change144
    25 to 293−7.43Little change144
    30 to 3444.50Little change144
    35 to 39513.88Little change144
    40 to 44623.02Little change144
    15 to 191−12.97Largest gains144
    20 to 242−4.05Largest gains145
    25 to 2935.80Largest gains145
    30 to 34419.11Largest gains145
    35 to 39524.75Largest gains145
    40 to 44639.26Largest gains145
    All four lines rise with mother's age. The line for the largest declines stays below zero until the oldest band, and the line for the largest gains is above zero from the third band. Groups are defined by the change in total births, so the figure splits each group's change by age and tests nothing.Note: The named counties are the 578 that CDC WONDER natality identifies in every year from 2018 to 2024: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. WONDER pools the births of every other county in a state into one row, so those counties are not in the named counties.Note: Counties are sorted into four groups of equal size by their percent change in total births from 2018 to 2024: the largest-decline group has falls of 8.8% or more, and the largest-gain group has gains of 2.6% or more. Births are full counts, so no interval is drawn; the groups are formed on the outcome, so an interval would not describe a draw of counties.Note: A county that withholds a band in 2018 or 2024 is left out of that band's point.Source: CDC WONDER natality, births in 2018-2024; full counts of births by mother's age; changes pooled over counties in each group

    The groups are formed on the change in total births, so the figure splits each group's change by age and does not test an explanation. A separate question is whether a county's age mix predicts its change. If every age band in a county changed at the all-county rate, the county's 2018 mix would imply a change in births to mothers aged 15 to 4415 to 44 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality between a fall of 8.9%8.9% percent of 2018 birthsEstimandfall implied by the county's 2018 age mix, 5th percentile across countiesn577 countiesWeightsnone (full count)Populationnamed counties at the 5th percentile of implied changePeriodbirths in 2018 and 2024SourceCDC WONDER natality and a fall of 1.3%1.3% percent of 2018 birthsEstimandfall implied by the county's 2018 age mix, 95th percentile across countiesn577 countiesWeightsnone (full count)Populationnamed counties at the 95th percentile of implied changePeriodbirths in 2018 and 2024SourceCDC WONDER natality at the 5th5th percentileEstimandpercentile used to describe the spread of county changes (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality and 95th95th percentileEstimandpercentile used to describe the spread of county changes (a definition)Weightsnone (definition)Populationnamed countiesPeriodall years (a definition)SourceCDC WONDER natality percentiles of counties. The observed changes run over a much wider range, from a fall of 16.6%16.6% percent of 2018 birthsEstimandfall in the county's births to mothers aged 15 to 44, 5th percentile across countiesn577 countiesWeightsnone (full count)Populationnamed counties at the 5th percentile of change in births to mothers aged 15 to 44Periodbirths in 2018 and 2024SourceCDC WONDER natality to a gain of 19.8%19.8% percent of 2018 birthsEstimandgain in the county's births to mothers aged 15 to 44, 95th percentile across countiesn577 countiesWeightsnone (full count)Populationnamed counties at the 95th percentile of change in births to mothers aged 15 to 44Periodbirths in 2018 and 2024SourceCDC WONDER natality. The implied and observed changes have a correlation of −0.16 (95% CI −0.26 to −0.06)−0.16 correlation coefficientEstimandcorrelation, weighted by 2018 births to mothers aged 15 to 44, between the change in births that a county's 2018 age mix implies (each band changing at the all-county rate) and its change; county-cluster bootstrap intervalInterval95% CI −0.26 to −0.06n577 countiesWeights2018 births to mothers aged 15 to 44Populationnamed counties that publish all six age bands in 2018 and 2024Periodbirths in 2018 and 2024SourceCDC WONDER natality across 577577 countiesEstimandcount of countiesWeightsnone (full count)Populationnamed counties that publish all six age bands in 2018 and 2024Periodbirths in 2018 and 2024SourceCDC WONDER natality counties when counties are weighted by their births and −0.03 (95% CI −0.11 to 0.04)−0.03 correlation coefficientEstimandcorrelation, unweighted, one county one count, between the change in births that a county's 2018 age mix implies (each band changing at the all-county rate) and its change; county-cluster bootstrap intervalInterval95% CI −0.11 to 0.04n577 countiesWeightsnone (each county counts once)Populationnamed counties that publish all six age bands in 2018 and 2024Periodbirths in 2018 and 2024SourceCDC WONDER natality when each counts once. The oneone countiesEstimandcount of counties left out of the shift-share checkWeightsnone (full count)Populationnamed counties with a withheld age cell in 2018 or 2024Periodbirths in 2018 and 2024SourceCDC WONDER natality county that withholds an age cell is left out. A county's 2018 age mix therefore does not account for which counties lost births, and the weighted correlation is small and negative, so counties whose mix implied larger falls lost slightly less.

    What these data cannot show

    The chapter reports counts and shares of births and no rates. A birth rate needs the number of women of each age as its denominator, and the files staged for this book hold the total population of counties and tracts but not women by age. A fall in births to mothers aged 20 to 2420 to 24 years of ageEstimandage-of-mother range used in this chapter, from WONDER's five-year bands (a definition)Weightsnone (definition)PopulationmothersPeriodall years (a definition)SourceCDC WONDER natality can mean fewer births per woman, fewer women in that age group, or both, and so can a gain. County population estimates by age and sex from the Census Bureau would supply the denominator for age-specific rates. Births are counted in the mother's county of residence, so the map is not a map of fertility.

    County results describe the 578578 countiesEstimandcount of countiesWeightsnone (full count)Populationcounties that WONDER natality identifies in every year from 2018 to 2024 and that have birthsPeriodbirths in 2018 to 2024SourceCDC WONDER natality counties that WONDER identifies, those with 100,000100,000 residentsEstimandpopulation size at which WONDER identifies a county, applied to an earlier population vintage than the 2020 census (a definition)Weightsnone (definition)Populationcounties that CDC WONDER natality identifiesPeriodbirths in 2018 to 2024SourceCDC WONDER natality or more residents in its population vintage. They hold 79.4%79.4% percent of live births in the United StatesEstimandshare of births in the named countiesWeightsnone (full count)Populationlive births in the 50 states and DCPeriod2024SourceCDC WONDER natality of births in 2024, and the pooled rows lost fewer births, although those rows include counties that now exceed the line, so the named counties are not a sample of the country. WONDER's county files used here have no cut by the mother's race or Hispanic origin, so the chapter cannot say whether the shift in mothers' ages differs by group.

    The deprivation comparison is descriptive. The Area Deprivation Index describes neighborhoods in 2019 to 2023 and is averaged to counties, and region and deprivation overlap. The comparison of quartiles says nothing about why births fell in any county. It is an ecologicalEcological inferenceDrawing conclusions about individuals from data about places or groups. A pattern across counties need not hold for the people inside them. pattern, and it need not hold for the people inside the counties. The comparison of 2018 with 2024 uses the endpoint years only, and a county with few births moves from year to year by chance, so a county's direction of change is better established than its rank among the named counties.


    Data sources

    • CDC WONDER natalityCDC WONDER natality, county totals and county by mother's age, births in 2018 to 2024 (consolidated pulls); 2024 is finalYears: 2018-2024 · Weights: births in each county (pooled ratios of sums); changes and shares pooled over counties · License: Public domain (NCHS, CDC); WONDER data-use restrictions apply
    • Area Deprivation IndexNeighborhood Atlas Area Deprivation Index 2023 (v4.0.1), tract national rank, averaged to counties with 2019-2023 tract populationYears: 2023 release (version 4.0.1; built on ACS 2019-2023) · Weights: 2019-2023 tract population · License: Free for non-commercial use; cite the Neighborhood Atlas and Kind and Buckingham

    All data sources

    Methods

    This chapter compares births from 2018 to 2024 across the 578 counties that CDC WONDER names individually in every year, a set chosen by population size in a vintage earlier than the 2020 Census and not by outcome, and across groups of those counties by deprivation quartile and region. The figures are counts and shares of births, not birth rates, because no file used here holds women by age for counties, and births by mother's age use six of nine bands because most cells of the youngest and oldest bands are withheld. Pooled changes weight each county by its births, and counties that WONDER pools into an Unidentified Counties row have no county value. Births are full counts, so the intervals show dependence on which counties are in a group and not sampling error.

    Which births and counties are used

    Births are counts from CDC WONDER natality for 2018 to 2024 (2024 is final), by county of the mother's residence. The 578 named counties are the counties that WONDER identifies in every year and that have births in every year: counties with 100,000 or more residents in the population vintage WONDER uses, which is earlier than the 2020 Census. By 2020 Census population 27 counties outside Connecticut that have 100,000 or more residents are still pooled, and one named county is below it.

    WONDER pools every other county in a state into one Unidentified Counties row (49 rows), which is used only for the comparison of the named counties with the rest of the country. WONDER lists two further identifiers in every year with no births (Cape May County NJ, Portsmouth city VA), which are left out. The panel is defined by size, not by outcome, and every named county appears in all seven years. County totals have no withheld cell.

    Figures explained here: Figure 1 and Figure 2

    How births by mother's age and withheld cells are handled

    Births by mother's age come in nine bands. WONDER withholds cells of 1 to 9 births. A withheld cell is missing: it leaves the numerator and the denominator, which is the births in the published cells, and nothing is derived from a county total minus the published cells.

    The six bands from 15 to 19 through 40 to 44 have 11 withheld cells of 24,276, which could hold at most 99 births. The under-15 band and the 45-and-over bands are left out because most of their cells are withheld (6,594 of 12,138); the published tail cells hold 0.26% of births and the withheld ones at most 0.29%.

    A share is the births to mothers in an age range over births in the published cells for mothers aged 15 to 44, pooled over counties. A change in a band compares the counties that publish the band in both 2018 and 2024. No rate is computed: no file used here holds women by age for counties.

    The shift-share check applies the all-county change of each age band to each county's 2018 age mix and correlates the implied change with the observed change in births to mothers aged 15 to 44.

    Figures explained here: Figure 6, Figure 7 and Figure 8

    How counties are ranked, grouped and weighted

    A tract's Area Deprivation Index national rank is the unweighted mean of the ranks of its block groups. A county's deprivation rank is the mean of its tracts' ranks weighted by 2019-2023 tract population, with Connecticut tracts assigned to the eight legacy counties; quartiles hold equal numbers of the named counties. Regions are the four Census Bureau regions (the South has 16 states and DC).

    Pooled changes, shares and differences are ratios of sums over counties, so they weight each county by its births.

    The map draws every county of the book's county map; counties that WONDER does not name have no value.

    Figures explained here: Figure 4, Figure 5 and Figure 2

    What the intervals do and do not show

    Births are full counts, so these intervals show dependence on which counties are in a group and not sampling error. A region-by-quartile cell with fewer than 10 counties shows no interval, because a bootstrap over so few counties is mechanical. The groups of counties formed by the change in total births are defined on the outcome and carry no interval.

    How the bootstrap intervals are computed

    Pooled changes, shares and differences carry 95% percentile intervals from a bootstrap that resamples whole counties (2,000 replicates, seed 12345), with the same draws for every statistic so that a difference has its own interval. Correlations and slopes use a county-cluster bootstrap.

    References

    1. Osterman, Michelle J. K.; Hamilton, Brady E.; Martin, Joyce A.; Driscoll, Anne K.; Valenzuela, Claudia P. (2026). Births: Final Data for 2024. National Vital Statistics Reports 75(2). doi:10.15620/cdc/252440
    2. Kearney, Melissa S.; Levine, Phillip B.; Pardue, Luke (2022). The Puzzle of Falling US Birth Rates since the Great Recession. Journal of Economic Perspectives 36(1): 151-176. doi:10.1257/jep.36.1.151
    3. Kind, Amy J. H.; Buckingham, William R. (2018). Making Neighborhood-Disadvantage Metrics Accessible: The Neighborhood Atlas. New England Journal of Medicine 378(26): 2456-2458. doi:10.1056/NEJMp1802313
    4. Mathews, T. J.; Hamilton, Brady E. (2016). Mean Age of Mothers is on the Rise: United States, 2000-2014. NCHS Data Brief No. 232. www.cdc.gov/nchs/products/databriefs/db232.htm

    How to cite

    @misc{singh2026wherebirthsarefalling,
      author = {Singh, Vishal},
      title = {Where births are falling},
      year = {2026},
      url = {https://vishalsingh.org/zipcode/where-births-are-falling},
      note = {In ZIP Code Destiny. Published 9 October 2026.}
    }