US Abortion Bans and Infant Mortality

Abstract

Importance: The impact of recent abortion bans on infant mortality is not fully understood. There is also limited evidence on how these bans may interact with long-standing racial and ethnic disparities in infant health.

Objective: To examine the association of abortion bans with changes in infant mortality and to compare this association in racial and ethnic groups based on analyses within and across states.

Design, setting, and participants: This population-based, serial, cross-sectional study used a bayesian panel model to examine infant mortality rates in 14 states that implemented complete or 6-week abortion bans and compared them with predictions of infant mortality rates based on pre-ban mortality rates and states without bans. Data included all live births and infant deaths from all 50 US states and the District of Columbia for 2012 through 2023. Models accounted for temporal trends and state-specific factors, with analyses stratified by race and ethnicity, timing of death, and cause of death.

Exposure: Complete or 6-week abortion bans.

Main outcome and measures: Infant mortality rate, analyzed overall and by subgroups.

Results: The analysis found higher than expected infant mortality in states after adoption of abortion bans (observed vs expected, 6.26 vs 5.93 per 1000 live births; absolute increase, 0.33 [95% credible interval (CrI), 0.14-0.51]; relative increase, 5.60% [95% CrI, 2.43%-8.73%]). This resulted in an estimated 478 excess infant deaths in the 14 states with bans during the months affected by bans. The estimated increases were higher among non-Hispanic Black infants compared with other racial and ethnic groups, with 11.81 observed vs 10.66 expected infant deaths per 1000 live births, an absolute increase of 1.15 (95% CrI, 0.53-1.81) and relative increase of 10.98% (95% CrI, 4.87%-17.89%). The observed infant mortality rate due to congenital anomalies was 1.37 vs 1.24 expected (absolute increase, 0.13 [95% CrI, 0.04-0.21]; relative increase, 10.87% [95% CrI, 3.39%-18.08%]), while the rate not due to congenital anomalies was 4.89 observed vs 4.69 expected (absolute increase, 0.20 [95% CrI, 0.02-0.38]; relative increase, 4.23% [95% CrI, 0.49%-8.23%]). Texas had a dominant influence on the overall results and there were larger increases in southern vs nonsouthern states.

Conclusions: US states that adopted abortion bans had higher than expected infant mortality after the bans took effect. The estimated relative increases in infant mortality were larger for deaths with congenital causes and among groups that had higher than average infant mortality rates at baseline, including Black infants and those in southern states.

Figure 1.. Trends in Biannual US Infant Mortality Rates, 2012-2023

Infant mortality was measured as deaths of infants younger than 1 year per 1000 live births. Jagged lines show biannual infant mortality rates. Solid lines show smoothed infant mortality rates (locally estimated scatterplot smoothing with a span of 0.5). Vertical dotted lines represent when abortion ban exposures began in Texas and in other states. Texas imposed a 6-week abortion ban the year prior to other states’ bans; thus, its trendline is presented separately. Data are from birth and death certificates for all 50 US states and the District of Columbia obtained via the US Centers for Disease Control and Prevention’s WONDER database.

Figure 2.. Estimated Difference in Cumulative Observed vs Expected Infant Deaths in All US States With Abortion Bans in Months Affected by Bans

CrI indicates credible interval. Infant mortality was measured as deaths of infants younger than 1 year; neonatal mortality was measured as deaths at younger than 28 days. Congenital malformations are structural or functional anomalies that occur before birth and were identified as the cause of death via International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) codes Q00-Q99. Expected differences were computed using a bayesian hierarchical panel data model and compared observed data with counterfactual predictions of infant mortality rates based on pre-ban mortality rates for states with bans and on mortality rates for the entire period for states without bans. Data are from birth and death certificates for all 50 US states and the District of Columbia obtained via the US Centers for Disease Control and Prevention’s WONDER database. ^aIndicates 95% CrI excludes 0. ^bRacial and ethnic data were obtained from death certificates; identified by the next of kin, coroner, or other person who certified the death.

Figure 3.. Estimated Difference in Cumulative Observed vs Expected Infant Deaths Overall in US States With Abortion Bans, US States With Abortion Bans Excluding Texas, and Individual States in Months Affected by Bans

CrI indicates credible interval. Infant mortality was measured as deaths of infants younger than 1 year; neonatal mortality was measured as deaths at younger than 28 days. Congenital malformations are structural or functional anomalies that occur before birth and were identified as the cause of death via International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) codes Q00-Q99. Expected differences were computed using a bayesian hierarchical panel data model and compared observed data with counterfactual predictions of infant mortality rates based on pre-ban mortality rates for states with bans and on mortality rates for the entire period for states without bans. Data are from birth and death certificates for all 50 US states and the District of Columbia obtained via the US Centers for Disease Control and Prevention’s WONDER database. ^aIndicates 95% CrI excludes 0.