Abstract: BACKGROUND:Increasing rates of maternal opioid use disorder has led to greater number of opioid exposed newborns (OENs). Maternal enrollment in medication for opioid use disorder (MOUD) program improves short term neonatal outcomes. This study aimed at assessing neurobehavioral outcomes for OENs. METHODS:Retrospective observational cohort study of OENs between Jul 2006 and Dec 2018. Two study groups were identified as initiation of medication for opioid use disorder (MOUD) prior to diagnoses of pregnancy or after. Primary outcome variables were enrollment in and duration of EI services. Secondary outcome variable was diagnoses of a behavioral and/or developmental disorder (BDD) during the study period. RESULTS:Of 242 infants, 113 were enrolled in EI and BDD diagnoses data was available for all infants [age range 6 to 12 years], 82% infants had exposure to maternal MOUD, while 18% were exposed to either maternal prescription non-MOUD opioids or illicit opioids. Maternal MOUD initiation prior to pregnancy was associated with improved short term outcomes for OENs. Almost a third of infants were diagnosed with a BDD with no differences between the two study groups. CONCLUSION:Early initiation of maternal MOUD improved short term outcomes and discharge disposition for OENs. Prolonged in-utero exposure to opioids presents a potential for negative impact on neurodevelopmental and behavioral outcomes. These risks must be considered to increase access and adherence to EI services, as well as to focus on non-opioid based maternal MOUD. Longitudinal studies assessing the safety of MOUD on short and long-term child health outcomes are needed.