For Tegretol taken in the first trimester, the overall risk of a major malformation was 3.3 percent, the study authors reported.
The same group of researchers found in another study, published this year in the New England Journal of Medicine, that women taking valproic acid were six times more likely to have an infant with spina bifida and seven times more likely have an infant with hypospadias, compared with women using other anti-epileptic drugs.
The researchers agree with a recommendation from the American Academy of Neurology that valproic acid should be avoided in pregnancy if possible.
Dr. Orrin Devinsky, director of the Epilepsy Center at NYU Langone Medical Center, said that "for women of childbearing age, these drugs represent a risk."
Women need to balance the risk and benefit of these drugs, he explained. Women with epilepsy need to stay on an anti-epileptic drug while they are pregnant, Devinsky said.
"The risk of seizure to themselves and potentially to their fetus is greater than the risk of anti-epileptic drugs," he added.
There are alternative drugs, specifically lamotrigine (Lamictal) and levetiracetam (Keppra). However, there is little data on any dangers associated with these drugs during pregnancy, Devinsky noted.
Another expert, Dr. Kimford Meador, a professor of neurology at Emory University School of Medicine, said women need to know the risks associated with Tegretol.
"If a woman is of childbearing potential and you are prescribing this drug, that's when the conversation needs to occur," Meador said.
For more information on epilepsy, visit the U.S. National Library of Medicine.
SOURCES: Lolkje de Jong-van den Berg, Ph.D., Pharm.D., Division of Pharmacy, University of Groningen, the Netherlands; Orr
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