Outcome of children exposed in utero to antiepileptic drugs: Special emphasis on carbamazepine

Convulsions during pregnancy may impose various risks to the mother as well as to the developing fetus; epileptic women should therefore be treated during pregnancy. The children born to these women have a higher than normal rate of congenital anomalies. The drugs used may induce fetal antiepileptic drug effects. Of the various antiepileptic drugs, phenytoin seems to be the most teratogenic, followed by carbamazepine and valproic acid. The other anticonvulsants such as phenobarbitone, primidone, ethosuximide, clonazepam, lamotrigine and gabapentin are not discussed in this review. These drugs are perhaps less teratogenic but they are used less often, and for some the information related to their effects on the developing fetus is incomplete. At least some of the effects of the anticonvulsants on the developing fetus are dependent upon genetic factors (i.e. activity of epoxide hydrolase). It may be possible by using appropriate means for antenatal diagnosis to determine which fetuses are at high risk of developing the fetal antiepileptic drug effects. We emphasize that anticonvulsants should not be used for pregnant women with psychiatric disorders, as most psychoactive drugs are less teratogenic.