ABSTRACT/SUMMARY Both gestational diabetes mellitus (GDM) and pregnancy-induced hypertension (PIH) affect pregnancy, birth outcomes, and postpartum care. They are independent risk factors for diabetes mellitus (T2DM), hypertension (HTN), and mental health conditions such as postpartum depression (PPD). Despite recommendations that postpartum care should include blood pressure (BP), blood glucose (BG) monitoring, and PPD screening, current postpartum care practices have low screening rates, especially among Medicaid beneficiaries. While Medicaid covers nearly half of deliveries in the United States, many women lose coverage 60 days after birth. The American Rescue Plan Act of 2021 provided states with federal funding to extend postpartum coverage up to 12 months – Louisiana has done so while Mississippi has not. Additionally, on August 1, 2022, Louisiana enacted a statewide mandate requiring providers of postnatal care to screen for PPD and related mental health disorders. Using our collaboration with the Praxis project and combined expertise, we propose to evaluate the effects of the Medicaid postpartum extension (MPE) and PPD screening mandate on screening behaviors, health outcomes, and patient experiences in Louisiana (LA) compared to Mississippi (MS) over three periods (early 2022-2023, middle 2024-2025, and late 2026-2027). We will link electronic health records and Medicaid claims data in Louisiana and Mississippi, allowing us to track screening and follow-up care even after losing Medicaid coverage after delivery. The primary effectiveness measure will be a 3-month composite screening rate for BP, BG, and PPD. Secondary measures include individual screening rates, diagnoses, and management of T2DM, HTN, and PPD. The overall goal is to evaluate effective implementation strategies that aim to improve maternal postpartum health in Medicaid beneficiaries with GDM or PIH. To achieve this goal, the study will have three specific aims. First, we will examine the effectiveness of Louisiana’s MPE and PPD screening mandate on the rates of BG and BP monitoring, PPD screening, rates of T2DM, HTN, and PPD diagnoses, T2DM, HTN and PPD management, health disparities, and health care utilization, as compared to counterparts in Mississippi. The second aim will be to examine the cost-effectiveness and distributional cost-effectiveness of Louisiana’s MPE and PPD screening mandate from the patient, provider, payer, and social perspectives. The third aim will be to examine the complex contextual factors that influence adopting and implementing MPE and PPD screening mandates, and subsequent impacts on healthcare delivery, healthcare utilization, and maternal health within and between Louisiana and Mississippi.