PROJECT SUMMARY/ABSTRACTThe prevalence of opioid use disorder (OUD) during pregnancy has increased by nearly 500% over the past 15years. While pregnancy presents a strong motivation for seeking and complying with OUD treatment thepostpartum period is associated with a high risk for relapse. Indeed up to 80% of women with OUD relapse toillicit opioid use within six months of delivery. Relapse leads to a wide range of negative health and socialoutcomes for both the infant mother and entire family such as physical (e.g. fatal and non-fatal overdoseincreased risk of substance use disorders in children) emotional (e.g. anxiety depression) and social (e.g.foster care placement poor academic achievement) consequences. Unfortunately little research is available onhow to prevent postpartum opioid relapse. A wide-range of hormones (e.g. cortisol progesterone oxytocin)have been linked to substance use disorders and infant caregiving activities. While hormones have the potentialto significantly reduce the risk for postpartum relapse methodological limitations (e.g. single hormoneassessment limited time assessment) content limitations (e.g. opioid use polysubstance use) and a lack ofdissemination of knowledge across disciplines are all limiting this use of this potentially highly impactfulapproach. Therefore my overall goal is to use new technologies and methodologies to directly address thecurrent limitations and enhance the cross-discipline dissemination of knowledge to utilize hormonallevel(s)/pattern(s) to protect against opioid relapse during the high-risk postpartum period. To achieve this goalthis New Innovator Award will address four objectives: (1) measure hormones infant caregiving activitiesrelapse risk factors and OUD-related outcomes during the postpartum period using a prospective cohort studydesign (2) identify hormonal level(s)/pattern(s) that are predictive of postpartum opioid use via with data-drivenpredictive analytics (3) examine methods to elicit/identify targeted hormone level(s)/pattern(s) using specificinfant caregiving activities exogenous hormone delivery and/or continuous/frequent hormone monitoring and(4) preliminarily assess the link between the identified hormonal level(s)/pattern(s) and OUD-related outcomes.Upon completion of this high-risk/high-reward project I will either (a) be able to rule out a hormonally-basedintervention as an element of a comprehensive behavioral-psycho-social approach to prevent postpartum opioidrelapse or (b) have strong preliminary evidence for the use of hormone level(s)/pattern(s) to prevent postpartumopioid relapse. Further this work will be ripe for expansion to other substances of abuse (e.g. cannabis) as wellas application to other postpartum health issues (e.g. depression anxiety).