Fetal growth in the offspring of epileptic women: results of an Italian multicentric cohort study.

An historical cohort study of the association between maternal epilepsy, anticonvulsant drugs and fetal growth was carried out among 47 hospitals collaborating in the Italian Multicentric Registry on Birth Defects (IPIMC). Birth weight, head circumference and body length were studied in 164 babies of epileptic women and compared to 185 controls. Seventy-nine epileptic women were treated by monotherapy, 59 by polytherapy and 26 took no anticonvulsant during pregnancy. An intrauterine growth retardation and a smaller head circumference was observed among babies of epileptic women. No effect was evident for body length. When specific anticonvulsant therapies were taken into account, only phenobarbital showed an effect on birth weight and head circumference; a reduction in head circumference was observed also in the babies of untreated epileptic women. The other antiepileptics (carbamazepine and valproic acid) showed no influence on the outcome considered. The observed effects on fetal growth can be interpreted as a result of an interaction between the effect of the maternal disease and that of the anticonvulsants.