Antiepileptic drug use in women of childbearing age.

Research on antiepileptic drug (AED) teratogenesis has demonstrated an increased risk for valproate. The impact of these findings on current AED prescribing patterns for women of childbearing age with epilepsy is uncertain. The Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) Study is an ongoing prospective multicenter observational investigation that enrolled pregnant women with epilepsy on the most common AED monotherapies from October 1999 to February 2004 (carbamazepine, lamotrigine, valproate, and phenytoin). A 2007 survey of AED use in women of childbearing age at eight NEAD centers found a total of 932 women of childbearing age with epilepsy (6% taking no AED, 53% monotherapy, 41% polytherapy). The most common monotherapies were lamotrigine or levetiracetam. Since 2004, prescriptions of carbamazepine, phenytoin, and valproate have decreased, whereas those for levetiracetam have increased. Except for the top two AED monotherapies, there were marked differences in other monotherapies and in polytherapies between U.S. and UK centers. Future investigations are needed to examine reasons for drug choice.