The impact of cocaine on pregnancy and neonatal outcome has been well documented over the past few years, but little information regarding long-term outcome of the passively exposed infants has been available. In the present study, the 2-year growth and developmental outcome for three groups of infants is presented: group 1 infants exposed to cocaine and usually marijuana and/or alcohol (n = 106), group 2 infants exposed to marijuana and/or alcohol but no cocaine (n = 45), and group 3 infants exposed to no drugs during pregnancy. All three groups were similar in racial and demographic characteristics and received prenatal care through a comprehensive drug treatment and follow-up program for addicted pregnant women and their infants. The group 1 infants demonstrated significant decreases in birth weight, length, and head circumference, but by a year of age had caught up in mean length and weight compared with control infants. The group 2 infants exhibited only decreased head circumference at birth. Head size in the two drug-exposed groups remained significantly smaller than in control infants through 2 years of age. On the Bayley Scales of Infant Development, mean developmental scores of the two groups of drug-exposed infants did not vary significantly from the control group, although an increased proportion of group 1 and 2 infants scored greater than two standard deviations below the standardized mean score on both the Mental Developmental Index and the Psychomotor Developmental Index compared with the control infants. Cocaine exposure was found to be the single best predictor of head circumference. Across all infants in the study, a significant correlation between small head size and developmental scores was found. The present study demonstrates that intrauterine drug exposure may place infants at risk for developmental outcome and that head growth after birth may be an important biological marker in predicting long-term development in children exposed in utero to cocaine and other drugs.
- Received May 22, 1991.
- Accepted June 26, 1991.
- Copyright © 1992 by the American Academy of Pediatrics