Effects of Cocaine on the Placenta

Adverse perinatal outcomes of gravidas using cocaine is well documented, but the effects on the placenta have been difficult to elucidate due to confounding factors such as concurrent use of other drugs. This study compares pathologic findings of 26 placentas from women who used only cocaine during pregnancy with findings from 26 controls. All women were from a similar socio-economic class and were controlled for gestational age and tobacco use. None of the cocaine placentas were from women whose toxicology screens were positive for drugs other than cocaine.

In the 26 cocaine placentas, there was 1 infarct, 3 chronic villitis, and 1 segmental fibrosis, with none present in the controls. In the control group, there was 1 decidual vasculopathy and 1 thrombus in a maternal vessel, but none were in the cocaine placentas. Each group had 1 thrombus in a fetal vessel. The study group showed 6 cases of chorioamnionitis and 1 funisitis; the control group had 10 and 4 cases, respectively. None of the above or seven other features showed a statistically significant difference between the cases and controls. Cocaine is a potent vasoconstrictive agent that blocks re-uptake of norepinephrine at the adrenergic nerve terminals. Our study suggests that cocaine does not cause an increased incidence of any of the 15 clearly recognizable placental features examined.