The Effects of Opioid Use during Pregnancy on Infant Health and Well-Being.

In this study, we estimate the first causal effects of in utero opioid exposure on infant health at birth and child protective services reports. We employ maternal fixed-effects models using linked administrative data capturing 259,723 infants born to 176,224 mothers enrolled in Medicaid between 2010 and 2019. Our preferred specifications suggest that neonatal abstinence syndrome and NICU admission bear strong associations with prenatal opioid exposure, concentrated on illicit and medication assisted treatment (MAT) exposure in the first and third trimesters. We find that prenatal opioid exposure is associated with increased CPS reports, low birth weight, preterm birth, and small for gestational age, though these measures are less sensitive with respect to the timing of exposure. While we detect relatively smaller effects of non-MAT prescription opioid exposure on NAS, NICU admission, low birthweight, these effects are not trivial, suggesting that medical professionals should consider balancing the potential for adverse side effects of infants with the benefits of pain management for pregnant women.