Adverse perinatal outcome in parturients who use crack cocaine

To determine the risk of adverse pregnancy outcome among crack cocaine users in a large homogeneous prenatal population with objective documentation of drug use.

A retrospective cohort study was performed on a population of inner-city women who were offered routine voluntary urine drug screening and who delivered between January and December 1992 at a large county hospital. The study population consisted of 483 users (positive drug screens) and 3158 non-users (negative drug screens). Univariate analysis and multiple logistic regression were used to identify the relation between crack cocaine use and adverse perinatal outcome.

Users were significantly more likely than nonusers to deliver low birth weight (LBW) infants (31.3% versus 14.9%; crude odds ratio [OR] 2.6; 95% confidence interval [CI] 2.1, 3.2), growth-restricted infants (29.0% versus 13.0%; crude OR 2.7; 95% CI 2.2, 3.4), and preterm infants (28.2% versus 17.1%; crude OR 1.9; 95% CI 1.5, 2.4). In addition, users were more likely to have abruptions (3.3% versus 1.1%; crude OR 3.0; 95% CI 1.6, 5.6) and infants with low 5-minute Apgar scores (7.9% versus 4.5%; crude OR 1.8; 95% CI 1.2, 2.7). After adjusting for confounders (including alcohol use and smoking), only the risks of LBW and fetal growth restriction (FGR) remained significant, with adjusted OR 1.6 (95% CI 1.03, 2.4) and adjusted OR 1.7 (95% CI 1.2, 2.3), respectively. Although there was no significant difference in the rate of low 5-minute Apgar scores between users and non-users after controlling for confounders, users with a positive urine drug screen within 1 week of delivery were significantly more likely than non-users to deliver infants with low 5-minute Apgar scores: crude OR 2.4; adjusted OR 2.0 (95% CI 1.1, 3.7).

In this inner-city population, crack cocaine use is associated with adverse pregnancy outcomes, as noted by increased risks of LBW and FGR.