Impact of Abortion-limiting Legislation on Preterm and Early Term Birth in Atlanta, Georgia, 2020-2023

Abortion restrictions, including the United States Supreme Court decision in Dobbs v. Jackson Women's Health Organization , have led to higher rates of adverse pregnancy outcomes and stress among pregnant women. It remains unknown whether the Dobbs decision or subsequent state-level legislation influenced early births. We assessed changes in the weekly number of conceptions and rates of preterm birth (PTB) (<37 weeks) and early term birth (ETB) (37-38 weeks) following the Dobbs decision (leak of draft and official ruling) and Georgia House Bill (HB) 481.

We analyzed deliveries from hospitals affiliated with Emory University between 2020 and 2023. We calculated the weekly number of live-birth weekly pregnancy counts by the first day of gestation, the percentage of preterm and ETBs over time, and estimated hazard ratios (HR) for preterm and ETB in association with three events: leak of the Dobbs draft opinion, the Dobbs official ruling, and HB481 implementation.

Following the leak of the Dobbs decision, the number of pregnancy counts declined. Among pregnancies conceived following HB481 implementation, there was an increase in the risk of PTB (HR = 1.16, 95% confidence interval [CI] = 1.03, 1.29) and ETB (HR = 1.05, 95% CI = 0.99, 1.12). Similar patterns were observed following the leak of the Dobbs decision and the official ruling.

Among pregnancies conceived post-HB481 implementation, there was an increase in the risk of PTB. These findings suggest that abortion-related legal changes may influence fertility patterns and perinatal outcomes.