Medication Safety and Pregnancy Heavily Emphasized at AES Press Teleconference

By Adam Modzelesky
EpilepsyUSA staff
Posted: April 20, 2005

For four days hundreds of doctors and health care professionals attended dozens of seminars at the American Epilepsy Society conference in New Orleans. During that time various topics, ranging from recent developments in computational modeling to the latest in pediatric treatment of epilepsy, were discussed. But no topic was touched upon nearly as much as pregnancy and epilepsy.

At the end of conference, members of the media gathered to hear and ask questions about antiepileptic drugs, pregnancy risks and pregnancy registries. A panel of four experts answered these questions: Gregory L. Barkley, M.D., Louis B. Holmes, M.D., Kimford Meador, M.D., and Martha J. Morrell, M.D.

Phenobarbital and Valproic Acid Carry Highest Risks of Birth Defects

The most pertinent information to come out of the teleconference was that phenobarbital and valproic acid, two medications used to treat epilepsy, run the highest risks of causing birth defects.

During the panel's discussion, Meador, of the University of Florida, said that valproic acid should not be the first choice of treatment for women with epilepsy of child-bearing age. This, he admitted, is easier said than done, however, because sometimes valproic acid is the only medication successful at controlling a woman's seizures. It comes down to weighing the pros and cons, and in the opinion of the entire panel of doctors, controlling the seizures is paramount over all the risks involved.

"Seizures can kill the mother, especially during pregnancy," Meador said. "They can also kill the child. Convulsions can also impair the child's cognition."

Morrell offered a potential solution, saying that newer drugs should be prescribed whenever possible. She said that it was worth a try despite the fact that physicians cannot be absolutely positive of the drug's safety. Her optimism is due to the fact that the numbers concerning drug safety are, thus far, "very compelling and reassuring."

Pregnancy Registries Hope to Offer Answers, but First Need Birth Reports

Barkley, chair of the Epilepsy Foundation's professional advisory board, opened the session by giving some basic background on antiepileptic drugs. Of note was his reminder that antiepileptic drug prescriptions are not limited to epilepsy treatment. They are also prescribed for such ailments as mood disorders, pain control and migraine.

Barkley was followed by Morrell who expounded on Barkley's primary point. Morrell further touched on antiepileptic medication's other uses, and further stated that most doctors make their treatment decisions without sufficient outcome data. Morrell said that because of this, women's participation in pregnancy registries are of the utmost importance.

Holmes, of Harvard University , is the head of the North American registry for pregnant women. He said that one of the primary reasons data is not up to par is because not enough women are registering. That, in Holmes' opinion, is because word is not getting out via the media, and also because women have "free-floating anxiety because of fear of insurance companies."

According to Holmes, pregnant women who take antiepileptic medication have nothing to fear and should be encouraged to call pregnancy registries with results. If they do not, then pregnancy registries will never be capable of providing reliable information regarding pregnancy risks stemming from medications.

Holmes' concern over lack of media attention was somewhat alleviated as a result of this teleconference, as articles pertaining to the topics discussed were printed in the LA Times and on WebMD.com.

Birth Defect Risks: By the Numbers

About 2 percent of all infants are at risk of malformations at birth, so regardless of whether a pregnant woman is taking medication or not, there is always going to be a risk, according to Holmes.

The North American registry reports that heart defects are the most common malformations in infants, and valproic acid has had the most instances of birth defects (10.7 percent). Phenobarbital came in second with a rate of 6.5 percent. Common birth defects vary by racial group, Holmes added, however, in general, heart defects are the most common along with cleft palates and skeletal and kidney defects.

In regards to cognition, a study performed in Britain showed that children of mothers who took valproic acid had an increased risk of having a lower IQ. Researchers found that, on average, children whose mothers took the medication had IQs about 10 points lower than children whose mothers did not take the medication.

The toll-free number for the registry is (888) 233-2334, and the hotline is available in both Spanish and English-language versions.