Project Summary: Overall Postpartum hemorrhage (PPH) is a leading cause of maternal death and severe maternal morbidity (SMM) and disproportionately affects socially marginalized groups. We propose to create a Maternal Health Research Center of Excellence at Stanford University called PRIHSM (PReventing Inequities in Hemorrhage-related Severe Maternal morbidity). The goals of PRIHSM are to reduce PPH and associated SMM by reducing and addressing disparities in important precursors to PPH-related SMM and mortality: cesarean birth and iron deficiency anemia (IDA). The problem of maternal IDA is vastly under-appreciated yet it affects approximately 16% of pregnancies in the U.S.; rates are 3-4x higher among Black people and 1.5-2x higher among Latinx people compared to the rest of the population. This translates to higher rates of PPH-related SMM. We propose that by effectively addressing antenatal IDA and these disparities, we can reduce PPH-related SMM. Additionally, almost 1 in 3 U.S. births are by cesarean delivery, rates vary 10-fold across hospitals, and Black and Asian individuals have the highest prevalence of cesarean section among low-risk pregnancies. While cesarean section can be a lifesaving intervention when appropriate, it is associated with significant risks that include PPH. We propose that enhanced birth equity and reduced variability in obstetric management are important strategies in addressing disparities in cesarean-linked PPH and reducing PPH-related SMM. Thus, our Aims are to: Aim 1 (Project 1). Reduce antenatal IDA by developing, implementing, and disseminating a patient-informed Anemia Prevention Toolkit, which will standardize the evaluation, diagnosis, and treatment of IDA and reduce the prevalence of IDA and racial/ethnic disparities in IDA at birth admission and PPH-associated SMM. Aim 2 (Project 2). Reduce disparities in rates of primary cesarean birth and cesarean-linked PPH by conducting a mixed methods study to understand drivers of hospital-level disparities in these outcomes, and implementing a patient-informed Maternal Equity Guide. Our work will involve community-university partnerships focused on improving maternal health equity and be driven by perspectives of patients, providers, and healthcare leadership. Our work will provide training opportunities to build research and clinical expertise relevant to PPH, especially among individuals who represent diverse perspectives and experiences within academic and community-based settings, and underserved areas. We propose a bold yet achievable agenda that will affect a sustainable decline in PPH-related mortality and morbidity and disparities.