Congenital renal abnormalities in infants with in utero cocaine exposure.

To determine the incidence of renal abnormalities among infants exposed to cocaine in utero, we performed ultrasound studies of the genitourinary tract in 100 consecutive infants admitted to the full-term nursery whose mothers had a history of cocaine use during pregnancy and/or a maternal toxicology screen was positive for cocaine. Mean gestational age of the newborns was 38.4 +/- 2.1 weeks. Mean birth weight was 2,846 +/- 561 gm.; 26% of the patients were less than 2,500 gm. and 18% were small for gestational age. Symptoms of drug withdrawal were present in 47 patients. Two newborns had murmurs consistent with a ventricular septal defect. On ultrasonography, 1 newborn had a unilateral multicystic/dysplastic kidney and 1 had kidneys that were 2 standard deviations below normal in size. Based on our results routine renal ultrasound studies do not appear to be indicated in full-term newborns exposed in utero to cocaine.