Impact of Medicaid Expansion on Interpregnancy Interval

Medicaid expansion under the Affordable Care Act (ACA) improved access to reproductive health care for low-income women and birthing people who were previously ineligible for Medicaid. We aimed to evaluate if the expansion affected the risk of having a short interpregnancy interval (IPI), a preventable risk factor for adverse pregnancy outcomes.

We evaluated parous singleton births to mothers aged 19 or older from U.S. birth certificate data 2009-2018. We estimated the effect of residing in a state that expanded Medicaid access (expansion status determined at 60 days after the prior live birth) on the risk of having a short IPI (<12 months) using difference-in-differences (DID) methods in linear probability models. We stratified the analyses by maternal characteristics and county-level reproductive health care access.

Overall risk of short IPI was 14.9% in expansion states and 16.3% in non-expansion states. The expansion was not associated with a significant change in risk of having a short IPI (adjusted mean percentage point change 1.24 [-1.64, 4.12]). Stratified results also did not provide support for an association.

ACA Medicaid expansion did not have an impact on risk of short IPI. Preventing short IPI may require more comprehensive policy interventions in addition to health care access.