PROJECT SUMMARY The current opioid crisis in the United States is well documented, with prevailing disparities in maternal outcomes for pregnant women with opioid use disorder. Women with opioid use disorder (OUD) experience lower rates of prenatal healthcare utilization and increased rates of emergency room utilization. Further, in this population there are higher rates of comorbid conditions, prevailing sociodemographic and health disadvantages, and parenting disparities. Women with OUD report fewer social supports and relationships to help them during the transition to parenthood. Current healthcare models do not meet the needs of this vulnerable population, requiring novel approaches in the perinatal period such as doula engagement. Doula intervention in this population of parenting women with OUD is not well studied. This project seeks to evaluate doula engagement in women with OUD during the perinatal period to study its effect on healthcare utilization, maternal clinical birth outcomes and post-partum psychosocial health, and parenting domains. All study procedures will occur at the Maternal Addiction Treatment Education & Research (MATER) program at Thomas Jefferson University, one of the oldest, largest, and most comprehensive OUD treatment programs in the U.S. for pregnant and parenting women. Over the 2-year project period, up to 100 pregnant women in treatment for OUD at MATER will be enrolled into either a doula or non-doula cohort to be followed over their perinatal period. Differences in outcomes will be compared between the two groups. Quantitative and qualitative data will be collected from electronic health records, validated study assessments, semi-structured interviews, a demographic survey, and an observational parenting assessment. In Aim 1, we will evaluate how doula care engagement affects healthcare utilization of women in treatment for OUD during the perinatal period. In Aim 2, we will evaluate how doula care engagement affects birth outcomes and psychosocial health of women in treatment for OUD. Finally, in Aim 3, we will evaluate how doula engagement affects parenting domains in the mother child dyad, for those dyads affected by OUD. This project responds to AHRQ's special emphasis notice of interest for health services research on the opioid crisis (NOT-HS-18-015) and addresses the experience and outcomes of women and individuals living in an urban area, AHRQ priority populations. Given the prevalence of OUD across the U.S. and the disparities in healthcare utilization and maternal perinatal outcomes for pregnant women with OUD, we anticipate this research will be of significant impact.