"There is good evidence that valproate, whether used by itself or in combination with other medications, increases the risk of major birth defects, including cleft palate and spinal bifida," says guideline co-author Gary S. Gronseth, MD, vice chairman of neurology at the University of Kansas Medical Center in Kansas City.
Additionally, taking valproate during pregnancy has been linked to lower IQs in children, he tells WebMD.
The guidelines come on the heels of a study showing that women with epilepsy who took valproate during pregnancy gave birth to children whose IQ at age 3 averaged up to 9 points lower than the scores of children exposed to other epilepsy drugs.
In response to the guidelines, a spokesperson for Abbott, which makes valproate, said the drug may be the only effective medication for some women, but doctors and patients should discuss risks and benefits of treatment.
Pregnant women may also want to avoid taking the seizure drugs phenytoin (Dilantin) and phenobarbital, as they too have been linked to lower IQs in children, Gronseth says.
Epilepsy and Pregnancy
Gronseth and other panel members stress that pregnancy is safe for most women with epilepsy.
"Overall, what we found was very reassuring to woman with epilepsy planning to become pregnant," says lead guideline author Cynthia Harden, MD, director of the epilepsy division at the University of Miami's Miller School of Medicine.
"Contrary to previous dogma, women with epilepsy are not at a substantially increased risk of having a cesarean section, late pregnancy bleeding, or premature contractions or premature labor and delivery," she says.
Also, if a woman is seizure-free for nine months to one year before she becomes pregnant, it's likely that she will not have any seizures during the pregnancy -- even if she switches medications, Harden tells WebMD.
About 500,000 women of childbearing age in the U.S. have some form of epilepsy, which is characterized by brief disturbances of electrical activity in the brain, according to Harden. Three to five out of every 1,000 births are to women with epilepsy.