MHPAEA/ACA Policy Implementation and Severe Maternal Morbidity Among Commercially Insured Individuals, 2008-2019

INTRODUCTION: We aimed to identify rates and trends in severe maternal morbidity (SMM) in relationship to implementation of the Mental Health Parity and Addiction Equity Act (MHPAEA) and Affordable Care Act (ACA). METHODS: We conducted a serial, cross-sectional analysis among individuals with continuous commercial coverage in the year preceding and following an inpatient livebirth using data from Optum Cliniformatics Data Mart. We identified hospital deliveries and cases of SMM using standard methods. We excluded cases of SMM in which blood transfusion represented the only indicator of SMM. We evaluated rates and trends in SMM in both the implementation (2008–2014) and post-implementation (2015–2019) periods using an interrupted time-series model fit with generalized estimating equations for the overall population and compared those with and without perinatal mood and anxiety disorders (PMAD). The University of Michigan Institutional Review Board deemed this study exempt from review. RESULTS: The sample included 681,616 births. SMM decreased by 53.2% from 195.8 (95% CI, 188.1–203.3) to 91.6 (95% CI, 85.7–97.6) per 10,000 hospitalizations for birth between 2008 and 2019. We identified decreasing SMM rates in both periods, with a larger decrease in the post-implementation period (implementation marginal effects [ME], −0.0012; post-implementation ME, −0.0015; P <.001). We observed decreasing SMM rates in both periods for those with and without PMAD, with the steepest decline among those with PMAD in the post-implementation period. CONCLUSION: These data suggest that implementation of the MHPAEA and ACA may have had a role in decreasing rates of SMM among childbearing individuals with commercial insurance.