[Teratogenic risks of epilepsy and anticonvulsants]

This paper presents a review of the literature regarding the risks of birth defects in infants born of an epileptic mother or father. It appears that epileptic women on anticonvulsant drugs have a 2-3-fold greater risk of delivering a baby with a major malformation. The risk is more specific for facial clefts, congenital heart defects and spina bifida. The risk increase for mild anomalies, especially facial dysmorphology, is evaluated in a very variable manner (5-45%). The respective roles of the disease itself and its treatment are discussed; it seems likely that genes play a part in the general risk increase, but that maternal epilepsy plays a more important role than paternal epilepsy, and that therefore a non-genetic mechanism exists. One hypothesis could conciliate all theories (genes, seizures during pregnancy, teratogenic effect of drugs), ie that of the existence of genetically-determined differing susceptibility to drugs. Monotherapy seems to induce a lower risk than polytherapy, and is thus to be preferred if clinically possible. Because of minor differences in teratogenic effect between drugs (with the exception of a more specific association between sodium valproate and spina bifida), choice should be determined by the particular therapeutic necessities, with suitable surveillance of the pregnancy.