Minor anomalies in children of mothers with epilepsy.

Minor anomalies are small, structural deviations that result from alterations in morphogenesis during gestation. Multiple minor anomalies are clinically significant, because they are associated with an increased risk of major developmental defects in the affected individuals. Children of mothers with epilepsy have an excess of minor and major anomalies as compared with the incidence in children of parents without epilepsy. Of the typical minor anomalies described in offspring of mothers with epilepsy, most features appear to be genetically linked with epilepsy. Only distal digital hypoplasia seems to be a specific marker for phenytoin teratogenicity. In most children, distal digital hypoplasia is not associated with serious developmental disorders. Genetic defects in the mechanisms of drug detoxification in the fetus and treatment of the mother with more than one antiepileptic drug during pregnancy increase the risk of severe teratogenic effects in offspring.