Birth defects risk appears low with newer-generation antiepileptics

First-trimester exposure to antiepileptic drugs compared with no exposure does not appear to increase the risk of major birth defects, according to a Danish study, published in the May 18 issue of the Journal of the American Medical Association.

Researchers studied 1,532 infants exposed to lamotrigine, oxcarbazepine, topiramate, gabapentin, or levetiracetam during the first trimester of pregnancy.  Forty-nine of these infants were diagnosed with a major birth defect compared with 19,911 infants who were not exposed to an antiepileptic drug.  Specifically, a major birth defect was diagnosed in 38 of 1,019 infants exposed to lamotrigine; in 11 of 393 infants exposed to oxcarbazepine; and in 5 of 108 infants exposed to topiramate.  Of the 59 infants exposed to gabapentin and the 58 exposed to levetiracetam, 1 and 0 infants were diagnosed with birth defects, respectively.

The researchers note that epilepsy during pregnancy is a therapeutic challenge.  Although the number of newly approved antiepileptic drugs has substantially increased since the 1990s, the data on first-trimester use of the newer-generation of therapeutic agents and birth defects are limited.