Unequal impacts of the COVID-19 pandemic on women's fertility preferences: Evidence from a longitudinal cohort in the United States

Trends in Short Interpregnancy Interval Births in the United States, 2016-2022

OBJECTIVE

To measure contemporary trends in the prevalence of short interpregnancy interval (IPI) births in the United States.

METHODS

We conducted a repeated cross-sectional analysis using 2016-2022 natality data from the National Vital Statistics System. We included all singleton live births to individuals with at least one prior live birth. We examined trends over time in short IPIs less than 18 months, as well as for specific durations within this time frame (less than 6 months, 6-11 months, and 12-17 months), using linear probability models that estimated changes in the prevalence of each IPI duration over time. We then estimated the prevalence of each short IPI duration by maternal race and ethnicity, socioeconomic characteristics (age, education, insurance payer at delivery), and geography (U.S. census region, state of residence).

RESULTS

The study sample included 14,770,411 singleton live births to individuals with at least one prior live birth in 2016-2022. Roughly a third (29.8%) of births had an overall IPI of less than 18 months (5.0% less than 6 months, 11.0% 6-11 months, and 13.8% 12-17 months). For IPIs less than 6 months, a slight statistical decline in prevalence was identified over the study period in unadjusted and adjusted models (adjusted annual percentage point change -0.02, 95% CI, -0.03 to -0.02). Slight statistical increases in the prevalence of IPIs of 6-11 and 12-17 months were identified in unadjusted models but were no longer significant and reversed direction in adjusted models, respectively. Long-standing inequities in the distribution of the shortest IPIs (less than 6 months) were stable compared with prior work across the indicators examined in this study.

CONCLUSION

Overall, it appears the prevalence of short IPIs has remained stable between 2016 and 2022.

Maternal Health During the COVID-19 Pandemic in the United States: An Interrupted Time-series Analysis

BACKGROUND

The COVID-19 pandemic, and subsequent policy responses aimed at curbing disease spread and reducing economic fallout, had far-reaching consequences for maternal health. There has been little research to our knowledge on enduring disruptions to maternal health trends beyond the early pandemic and limited understanding of how these impacted pre-existing disparities in maternal health.

METHODS

We leveraged rigorous interrupted time-series methods and US National Center for Health Statistics Vital Statistics Birth Data Files of all live births for 2015-2021 (N = 24,653,848). We estimated whether changes in maternal health trends after the onset of the COVID-19 pandemic (March 2020) differed from predictions based on pre-existing temporal trends. Outcomes included gestational diabetes, hypertensive disorders of pregnancy, gestational weight gain, and adequacy of prenatal care.

RESULTS

We found an increased incidence of gestational diabetes (December 2020 peak: 1.7 percentage points (pp); 95% confidence interval [CI]: 1.3, 2.1), hypertensive disorders of pregnancy (January 2021 peak: 1.3 pp; 95% CI: 0.4, 2.1), and gestational weight gain (March 2021 peak: 0.1 standard deviation; 95% CI: 0.03, 0.1) and declines in inadequate prenatal care (January 2021 nadir: -0.4 pp; 95% CI: -0.7, -0.1). Key differences by subgroups included greater and more sustained increases in gestational diabetes among Black, Hispanic, and less educated individuals.

CONCLUSION

These patterns in maternal health likely reflect not only effects of COVID-19 infection but also changes in healthcare access, health behaviors, remote work, economic security, and maternal stress. Further research about causal pathways and longer-term trends will inform public health and clinical interventions to address maternal disease burden and disparities.

Fertility in a Pandemic: Evidence from California

The COVID-19 pandemic was accompanied by social and economic changes previously associated with fertility delay and reduction, sparking widespread discussion of a "baby bust" in the U.S. We examine fertility trends using restricted vital statistics data from California, a diverse population of 40 million contributing 12% of U.S. births. Using time series models that account for longer-run fertility trends, we observe modest, short-term reductions in births from mid 2020 through early 2021. Birth counts in subsequent months matched or even eased the pace of fertility decline since the 2008 recession and are unlikely a function of the pandemic alone. Responses to the pandemic were heterogeneous. Fertility declined markedly among the foreign-born population, largely driven by changes in net migration. Among the U.S.-born population, the short-term pandemic-attributable reductions were largest among older, highly educated people, suggesting mechanisms of fertility reduction disparately accessible to those with the most resources. We find no evidence of a strong population fertility response to the pandemic's accompanying employment shock, providing additional evidence of a growing divide between macroeconomic conditions and fertility patterns in the U.S.

State-specific fertility rate changes across the USA following the first two waves of COVID-19

STUDY QUESTION

How did the first two coronavirus disease 2019 (COVID-19) waves affect fertility rates in the USA?

SUMMARY ANSWER

States differed widely in how their fertility rates changed following the COVID-19 outbreak and these changes were influenced more by state-level economic, racial, political, and social factors than by COVID-19 wave severity.

WHAT IS KNOWN ALREADY

The outbreak of the COVID-19 pandemic contributed to already declining fertility rates in the USA, but not equally across states. Identifying drivers of differential changes in fertility rates can help explain variations in demographic shifts across states in the USA and motivate policies that support families in general, not only during crises.

STUDY DESIGN, SIZE, DURATION

This is an ecological study using state-level data from 50 US states and the District of Columbia (n = 51). The study period extends from 2020 to 2021 with historical data from 2016 to 2019. We identified Wave 1 as the first apex for each state after February 2020 and Wave 2 as the second apex, during Fall/Winter 2020-2021.

PARTICIPANTS/MATERIALS, SETTING, METHODS

State-level COVID-19 wave severity, defined as case acceleration during each 3-month COVID-19 wave (cases/100 000 population/month), was derived from 7-day weekly moving average COVID-19 case rates from the US Centers for Disease Control and Prevention (CDC). State-level fertility rate changes (change in average monthly fertility rate/100 000 women of reproductive age (WRA)/year) were derived from the CDC Bureau of Vital Statistics and from 2020 US Census and University of Virginia 2021 population estimates 9 months after each COVID-19 wave. We performed univariate analyses to describe national and state-level fertility rate changes following each wave, and simple and multivariable linear regression analyses to assess the relation of COVID-19 wave severity and other state-level characteristics with fertility rate changes.

MAIN RESULTS AND THE ROLE OF CHANCE

Nationwide, fertility dropped by 17.5 births/month/100 000 WRA/year following Wave 1 and 9.2 births/month/100 000 WRA/year following Wave 2. The declines following Wave 1 were largest among majority-Democrat, more non-White states where people practiced greater social distancing. Greater COVID-19 wave severity was associated with steeper fertility rate decline post-Wave 1 in simple regression, but the association was attenuated when adjusted for other covariates. Adjusting for the economic impact of the pandemic (hypothesized mediator) also attenuated the effect. There was no relation between COVID-19 wave severity and fertility rate change following Wave 2.

LIMITATIONS, REASONS FOR CAUTION

Our study harnesses state-level data so individual-level conclusions cannot be inferred. There may be residual confounding in our multivariable regression and we were underpowered to detect some effects.

WIDER IMPLICATIONS OF THE FINDINGS

The COVID-19 pandemic initially impacted the national fertility rate but, overall, the fertility rate rebounded to the pre-pandemic level following Wave 2. Consistent with prior literature, COVID-19 wave severity did not appear to predict fertility rate change. Economic, racial, political, and social factors influenced state-specific fertility rates during the pandemic more than the severity of the outbreak alone. Future studies in other countries should also consider whether these factors account for internal heterogeneity when examining the impact of the COVID-19 pandemic and other crises on fertility.

STUDY FUNDING/COMPETING INTEREST(S)

L.G.K. received funding from the National Institute of Environmental Health Sciences (R00ES030403), M.C. from the National Science Foundation Graduate Research Fellowship Program (20-A0-00-1005789), and M.L. and E.S. from the National Institute of Environmental Health Sciences (R01ES032808). None of the authors have competing interests.

TRIAL REGISTRATION NUMBER

N/A.