Evaluation of anticonvulsant drugs during pregnancy in a population-based Hungarian study.

The Hungarian Case-Control Surveillance of Congenital Anomalies, from 1980-1987, involved 10,698 malformed cases and 21,546 non-malformed controls. Ninety-five pregnant women were treated by 144 anticonvulsants excluding diazepam and barbiturates. The rate of anticonvulsant use was 2.9 times higher in pregnant women having malformed offspring than in control mothers and this difference was greater in polytherapy than in monotherapy.