Level of in utero cocaine exposure and neonatal ultrasound findings

Objective. To assess whether there is an association between the level of i n utero cocaine exposure and findings on neonatal cranial ultrasound, contr olling for potentially confounding variables. Study Design. In a prospective longitudinal study, three cocaine exposure g roups were defined by maternal report and infant meconium assay: unexposed, heavier cocaine exposure (> 75th percentile self-reported days of use or o f meconium benzoylecogonine concentration) or lighter cocaine exposure (all others). Neonatal ultrasounds from 241 well, term infants were read by a s ingle radiologist who was masked to the exposure group. Results. Infants with lighter cocaine exposure did not differ from the unex posed infants on any ultrasound findings. After controlling for infant gend er, gestational age, and birth weight z scores and for maternal parity, blo od pressure in labor, ethnicity, and use of cigarettes, alcohol, and mariju ana during pregnancy, the more heavily cocaine-exposed infants were more li kely than the unexposed infants to show subependymal hemorrhage in the caud othalamic groove (covariate adjusted odds ratio: 3.88; 95% confidence inter val: 1.45, 10.35). Conclusions. This is the first study to demonstrate that ultrasound finding s suggestive of vascular injury to the neonatal central nervous system are related to the level of prenatal cocaine exposure. Inconsistency in previou s research in identifying an association between prenatal cocaine exposure and neonatal cranial ultrasound findings may reflect failure to consider do se effects.