Malformations in newborns associated to anticonvulsant consumption during pregnancy. experience in third level hospital of Mexico.

AIM The purpose of the present study is to determine the relationship between the anticonvulsant drug use during pregnancy and the presence of malformations in the newborns. METHODS The frequency of malformations in the neonates of epileptic mothers under anticonvulsant treatment was analyzed in two periods, one from 1988 to 1992, which included 76 epileptic mothers, and another from 1996 to 2003 with 170 patients. RESULTS In the first period, 51 (67.1%) of mothers received monotherapy and 25 (32.9%) received polytherapy of phenytoin with carbamazepine, valproic acid or phenobarbital. In this period, 4 newborns (16%) with congenital malformations were registered. In the second period, 159 (93.5%) of the epileptic mothers received monotherapy and 11 (6.5%) received polytherapy of valproic acid with carbamazepine or phenytoin. During this period only 3 newborns 27.3% with malformations were registered. DISCUSSION Clinical treatment should consider the risk of using polytherapy, mainly if phenytoin or valproic acid are combined with other anticonvulsants.