Postneonatal mental and motor development of infants exposed in utero to opioid drugs

We compared the mental and motor development of 33 infants from innercity, African American families whose mothers used opioid drugs during pregnancy with that of 45 infants from demographically comparable families where the mothers were not users of opioids. We found that during the first 2 years of life, the children exposed to opioid drugs showed poorer functioning on Bayley Scales mental and psychomotor development indices as well as on Infant Behavior Record ratings of mental and motor functioning. Although both groups of children performed in the normal range during infancy, both groups showed sharp declines in their developmental scores during the second year of life relative to norms. The poorer performance of the opioid-exposed group in mental development was related to social-environmental risk factors; in psychomotor development, to reduced birth weight.