In the online version of Archives Neurology, June 13, 2011, Doctors Holmes and colleagues from the Massachusetts General Hospital for Children and the Harvard School of Public Health, the Departments of Obstetrics and Gynecology and Pediatrics, Loyola University Health System, present results from an analysis of the North American Antiepileptic Drug Pregnancy Registry between February 1, 1997 and June 1, 2010. Information on antiepileptic drug use and demographic characteristics was collected in three telephone interviews across the United States and Canada. Six thousand eight hundred fifty-seven (6857) pregnant women taking an antiepileptic drug for any reason were included in the analyses. The investigators found that the risks of malformations was 1.9% amongst infants exposed to lamotrigine as the sole medication; however, it rose to 9.1% when lamotrigine was combined with valproic acid; 2.9% when lamotrigine was added to any other antiepileptic drug. The risk of malformations was 2.9% for infants exposed to carbamazepine as sole therapy, as opposed to 15.4% for carbamazepine with valproic acid, or 2.5% for carbamazepine with any other antiepileptic drug. The investigators concluded that the risks of malformations among infants exposed to lamotrigine and carbamazepine in combination was higher than whether these individuals took each of these medications as the sole finding.

This study is important because it is one of the few to address the issue of combination therapy and risks to unborn children, as opposed to single therapy, which is the way most pregnancy registries are reported. This study underscores the point that has been made by previous studies showing the risks associated with valproic acid use. It also shows that combination therapy also increases one’s risk for potential problems to occur. This is another important finding in our understanding of what are the risks to women with epilepsy who become pregnant while taking medication.

Joseph Sirven, M.D.
Editor-in-Chief, epilepsy.com 
Last Reviewed: 7/15/11 

Article from the June 2011 Epilepsy.com Spotlight Newsletter. Other articles in this issue inclue:

• Focus on Antiepileptic Drugs: Carbamazepine
• Surgical Treatment for Seizures in Children
• Who is at Risk for SUDEP?
• Who is Reading Your EEG? Should You Care?
• Morbidity and Mortality Following Surgery for Intractable Temporal Lobe Epilepsy in the United States
• Recently Published Results of U.S. Government-Sponsored Workshop on SUDEP