Cognitive and motor outcomes of cocaine-exposed infants

JAMA. 2002 Apr 17;287(15):1952-60. doi: 10.1001/jama.287.15.1952.


Context: Maternal use of cocaine during pregnancy remains a significant public health problem, particularly in urban areas of the United States and among women of low socioeconomic status. Few longitudinal studies have examined cocaine-exposed infants, however, and findings are contradictory because of methodologic limitations.

Objective: To assess the effects of prenatal cocaine exposure on child developmental outcomes.

Design: Longitudinal, prospective, masked, comparison birth cohort study with recruitment in 1994-1996.

Setting: Obstetric unit of a large US urban teaching hospital.

Participants: Four hundred fifteen consecutively enrolled infants (218 cocaine-exposed and 197 unexposed) identified from a high-risk, low-socioeconomic status, primarily black (80%) population screened through clinical interview and urine and meconium samples for drug use. The retention rate was 94% at 2 years of age.

Main outcome measures: The Bayley Mental and Motor Scales of Infant Development, assessed at 6.5, 12, and 24 months of corrected age.

Results: Controlled for confounding variables, cocaine exposure had significant effects on cognitive development, accounting for a 6-point deficit in Bayley Mental and Motor Scales of Infant Development scores at 2 years, with cocaine-exposed children twice as likely to have significant delay (mental development index <80) (odds ratio, 1.98; 95% confidence interval, 1.21-3.24; P =.006). For motor outcomes, there were no significant cocaine effects.

Conclusions: Cocaine-exposed children had significant cognitive deficits and a doubling of the rate of developmental delay during the first 2 years of life. Because 2-year outcomes are predictive of later cognitive outcomes, it is possible that these children will continue to have learning difficulties at school age.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Apgar Score
  • Birth Weight
  • Cocaine-Related Disorders / complications*
  • Cognition*
  • Developmental Disabilities / epidemiology*
  • Developmental Disabilities / etiology
  • Female
  • Gestational Age
  • Humans
  • Infant
  • Longitudinal Studies
  • Male
  • Meconium / chemistry
  • Neuropsychological Tests
  • Pregnancy
  • Pregnancy Complications*
  • Prenatal Exposure Delayed Effects*
  • Psychomotor Performance*
  • Socioeconomic Factors
  • Statistics, Nonparametric