(220) Effect of the Dobbs decision on severe maternal morbidity in Wisconsin

Objective: With maternal mortality rates increasing in the US, efforts to reduce perinatal morbidity and mortality are imperative. Recent policy changes have restricted abortion access which is a pillar of perinatal care. Wisconsin (WI) was significantly affected by the Dobbs decision. The aim of this study is to examine the effect of the Dobbs decision on the rate of severe maternal morbidity (SMM) in WI.

Study Design: A retrospective cohort of all births from 1/1/2021 to 11/1/2023 in WI was constructed using Wisconsin Hospital Association coding data. Pre Dobbs was defined as 1/1/2021 – 6/23/2022 and post Dobbs was defined as 6/24/2022 – 11/1/2023. Generalized additive logistic regression models were constructed for the change in the SMM rate as a function of geographic location (ZIP code). Statistical analyses were performed using the mgcv package in R.

Results: There were 160,649 births– 79,796 pre Dobbs and 80,853 post Dobbs and 8,426 SMM events (5.2%) – 4,148 (5.2%) pre Dobbs and 4,278 (5.3%) post Dobbs (RR 1.02, 95% CI 0.97-1.06, p=0.47). There was modest evidence (p=0.07) of geographic variation in the impact of the Dobbs decision on the SMM rate. There were nominally significant (p < 0.05) elevations in the SMM rate for 101 ZIP codes in southeast WI and nominally significant reductions in the SMM rate for 1 ZIP code in northwest WI.

Conclusion: There is little evidence for a statewide effect of the Dobbs decision and restricted abortion access on the rate of SMM in WI. However, there is modest evidence of geographic variation in the effect (a SE to NW gradient) with elevated rates of SMM in southeastern WI. Given that geographic variation exists, this suggests that location of residence may impact rates of SMM with limited abortion access during pregnancy. SMM should be evaluated in each state to identify vulnerable areas with limited abortion access. Future work will analyze all 2024 births as there may be more SMM given incomplete data for patients unrepresented in this data set, but affected by the Dobbs decision during early pregnancy.