Maternal Fetal Medicine Units Network: University of California, San Francisco - PROJECT SUMMARY Significant disparities in maternal and infant mortality and morbidity exist in the U.S, and the MFMU Network aims to reduce the rates of preterm birth, fetal growth abnormalities, newborn morbidity, and maternal complications of pregnancy. Novel strategies, including new therapies and technologies, innovative study designs and interventions, attention to implementation science, inclusion of adequately diverse study participants into clinical trials, and input from the stakeholders impacted by health disparities are needed to improve outcomes for pregnant and lactating people. Although California accounts for nearly one eighth of annual U.S. births, the MFMU Network lacks a West Coast site. The University of California, San Francisco (UCSF) has a racially and ethnically diverse patient population, including many individuals with differing gender identities. The inclusion of historically marginalized communities, including segments of the population that are highly represented in California, will ensure the MFMU Network study results are generalizable, and will promote health equity for all persons. UCSF is a pioneer in innovative research techniques, such as genomics and metagenomics, as well as clinical research methods, including community partnership and implementation science. In addition, UCSF has a robust research infrastructure that has supported numerous translational investigations including epigenetics and infection studies, metagenomic sequencing in pregnant patients with obstetric complications, studies of environmental contaminants such as wildfire smoke on reproductive outcomes, and placental biology, including the impact of COVID-19 and COVID vaccines. UCSF has an extensive network of affiliated practices and referring hospitals that provide care for diverse patient populations with a myriad of pregnancy- related complications and together with its affiliate, Zuckerberg San Francisco General Hospital, performs nearly 4000 deliveries per year in mostly high-risk patients. Therefore, to support the mission of the MFMU Network, we will 1) Enroll a large and uniquely diverse, west coast participant population; 2) Contribute multidisciplinary expertise of UCSF investigators to high priority areas of public health that impact pregnant people and/or their infants, such as the COVID pandemic, the opioid crisis, and the impacts of climate change; and 3) Leverage our affiliation with the MFMU Network to develop a diverse group of young academic investigators. UCSF will bring a host of novel and innovative opportunities, including clinical populations and unique technological and research approaches that will strengthen the work of the MFMU Network.