PROJECT SUMMARY Addressing the persistently high rates of severe maternal morbidity among Black women is an urgent public health priority. Of the 3.8 million U.S. births each year, nearly a third occur via cesarean delivery, which is a risk factor for severe maternal morbidity, and cesarean rates are higher among Black women than among White women. For women giving birth after a prior cesarean, maternal morbidity is lowest with a vaginal birth, but higher with an unplanned (vs. planned) repeat cesarean. There are racial and ethnic disparities in birth mode among women with a prior cesarean, with Black women more likely to have unplanned repeat cesareans compared to White women, but these disparities are poorly understood. The most common indications for primary cesarean are subjective and differ by race – suggesting potential differences in care quality and processes of care by race – but little is known about indications for unplanned cesarean among women with labor after cesarean. Prior work has also established that hospital characteristics are related to hospital rates of labor after cesarean utilization and vaginal birth after cesarean success, and that there is substantial hospital-level variation in maternal morbidity rates and racial and ethnic disparities in maternal morbidity rates. However, it is unclear how hospital characteristics and quality of care contribute to racial disparities in birth mode among women with a prior cesarean, and how Black women with a prior cesarean perceive their care. This mixed-methods study will use combined vital statistics and hospital discharge data and data from semi- structured interviews with Black women with a prior cesarean. The specific aims are: 1) To characterize the association between hospital characteristics and racial disparities in birth mode among women with a prior cesarean; and 2) To explore the experiences of perinatal care among Black women with a prior cesarean. Despite the higher risk of unplanned cesarean birth among Black (vs. White) women with a prior cesarean, little is known about why this occurs. Identifying factors and processes that contribute to these outcomes is particularly urgent given persistent racial disparities in severe maternal morbidity. Results from this study will contribute to a better understanding of the circumstances associated with labor after cesarean ending in cesarean delivery, and help to identify potential interventions to improve the quality of care for women with a prior cesarean.