Impact of

Research on in utero opioid exposure impacts has focused on Neonatal Opioid Withdrawal Syndrome (NOWS). However, possible impacts on fetal growth and newborn wellbeing have emerged, with inconsistencies likely driven by methodological issues. Our goal was to compare birth outcomes between newborns with prenatal opioid exposure and a matched control group.Participants were identifiedCompared to biochemically verified controls, exposed newborns had higher rates of fetal growth restriction, weighed less, had decreased length and head circumference, and had higher rates of respiratory distress, sepsis, and jaundice. No significant differences in gestational length, Apgar scores, or neonatal hypoglycemia were found. Adjusted regression analyses revealed that compared to controls, those exposed had an average 150 g decrease in birth weight, a two-fold increased risk for IUGR (OR = 2.09), a nearly three-fold (OR = 2.80) increased risk for jaundice, a more than seven-fold (OR = 7.40) increased risk for respiratory distress, and a thirty-fold (OR = 30.47) increased risk for sepsis.Results suggest significant pregnancy and newborn outcomes beyond NOWS following pregnancy opioid use, informing clinical screening and treatment decisions to enhance health and wellbeing in pregnancy, during the neonatal period, and beyond.