Is carbamazepine teratogenic? A prospective controlled study of 210 pregnancies.

The Israeli Teratogen Information Service prospectively followed up 210 pregnancies with first trimester carbamazepine exposure. Pregnancy outcome was compared with that of two overlapping controls, matched and general (n = 629), exposed to nonteratogenic agents. Our study suggests a twofold increase in the rate of major congenital anomalies (12/160 [carbamazepine] versus 18/560 [general control]; relative risk 2.24; 95% CI 1.1-4.56) and a birth weight reduction of approximately 250 g after in utero exposure to carbamazepine.