Pregnancy Registry Reps Announce Current Data, Need For More Births to be Reported

By Adam Modzelesky
betweenUs staff
Posted: April 13, 2005

Representatives of four world-wide pregnancy and antiepileptic drug registries recently spoke at the 58^th Annual Meeting of the American Epilepsy Society. Each individual's overriding message was that more reported pregnancies are needed to continue studies if they are to continue to serve as important sources of information as to how antiepileptic drugs affect pregnancy.

The four represented registries were: International Registry of Antiepileptic Drugs and Pregnancy (EURAP), the UK Epilepsy and Pregnancy Register, the Australian Pregnancy Registry of Women on Antiepileptic Drugs and the North American AED Registry.

EURAP

EURAP is the largest of all the pregnancy registries. Host to physicians representing 38 countries in E urope, Australia, Asia and South America, EURAP has actively collaborated and collected information on more than 5,800 pregnancies.

The primary goal of EURAP, according to its president Torbjorn Tomson, M.D., is to "compare the risk of major congenital malformations following maternal intake of different antiepileptic drugs and their combinations."

Tomson did not present any data that singled out which drugs might increase risks of major congenital malformations. However, he did report that the rates of malformations are reduced when the mother with epilepsy is taking one drug (6.2 percent) rather than multiple drugs (9.9 percent). He also reported the most commonly used drug in pregnant women with epilepsy is carbamazepine, followed by valproic acid, lamotrigine and phenobarbital.

UK Epilepsy and Pregnancy Register

John Craig, M.D., of the UK Epilepsy and Pregnancy Register, reported more promising news than that from EURAP regarding monotherapy vs. polytherapy. According to the UK registry, the risk of major congenital malformation while on one medication is 3.7 percent, while the risk of malformation while on multiple drugs is 6.1 percent.

Craig also reported that based on their near 3,800 reported pregnancies, the highest risk of abnormalities came from taking valproic acid (6.1 percent). He concluded by saying that though they need more pregnancies to be reported, the older antiepileptic drugs are associated with fetal malformations and abnormalities, and that animal studies are showing encouraging results for some of the newer antiepileptic drugs.

Australian Pregnancy Registry

Established in 1999, the Australian Pregnancy Registry has the fewest number of reported pregnancies of all: 630. Because of this, Cecilie Lander, M.D., the Australian registry's representative at the conference, proclaimed their dire need for women and physicians to call in reports.

Lander reported that their current data reflects very poorly on valproic acid. Their limited statistics show a staggering 38.5 percent risk of malformation in women taking more than 1,100 milligrams of valproic acid per day. On the other hand, women taking less than 1,100 milligrams per day show only a 5.4 percent risk.

Of the 630 participants, Lander said that only 22 had babies with malformations; 83 percent of the mothers had babies with no birth defects at all.

North American AED Registry

Lewis B. Holmes, M.D., of the North American Antiepilepsy Drug Pregnancy Registry, had the same message as the other registry representatives: they too need more pregnancies to study. But, he also reported something different. As is not the case with the other three registries, only mothers are allowed to phone and report to the North American AED Registry. According to Holmes, this has drastically hurt its pregnancy recruitment.

As of now, the North American AED Registry has more than 2,000 reported pregnancies, but Holmes said that it should be higher. He also said that upon calling, women must only fill out a consent form by mail and then give three interviews. The interviews are at enrollment, at 7 months gestation and, finally, at 2 months postpartum.

At the end of his presentation, Holmes, on behalf of the North American AED Registry, called out to the media and to physicians for help. He said that most women do not call and, in order for the registry to report correct data, more women must be encouraged to do so.

Study on Neurodevelopmental Effects of Antiepileptic Drugs

After all four registry representatives presented information, Kimford Meador, M.D., Melvin Greer Professor of Neurology at the University of Florida and director of its epilepsy and clinical alzheimer programs, spoke about the Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) study.

Meador said the study is examining mothers with both partial and generalized epilepsy, and he further reported a current enrollment of 361 women.

Out of all of those studied, valproic acid has been shown to be the most damaging drug. About 25 percent of cases involving serious adverse effects were due to valproic acid.

"I'd hate to see Valproate pulled from the market because it's an appropriate drug for most women," Meador said, "but it's not the drug of choice for pregnant women."