The frequency of cocaine abuse in pregnant women has increased markedly in the United States during the last decade. This increased abuse has lead to recognition of potentially negative perinatal outcomes. The purpose of this study is to determine the incidence of positive cocaine-specific screens in pregnant women and delivered infants at two Milwaukee area sites: an urban teaching hospital with a delivery base of 5,500 births annually and a suburban hospital with a delivery base of 1,700 births. A prospective, blinded analysis of urine specimens was performed at both sites over a 3-month period. All delivered infants, all women who presented to the labor and delivery unit and were discharged undelivered, and women who presented to the urban hospital's obstetrical clinic had urine samples obtained for toxicology analysis. Demographic data was also collected to include age, race, gestational age, and history of drug abuse. Results of the urine screen and demographic data were analyzed for frequency distribution. The overall incidence of positive cocaine screens was 3.5% in the urban population and less than 1% in the suburban population.