April 29, 2004 - Children born to women taking the commonly prescribed seizure medication Depakote are more likely to have birth defects and other problems. Researchers say that if possible women should avoid taking this medication during their childbearing years.
In the study, presented at the annual meeting of the American Academy of Neurology, researchers showed these problems were more common when women took Depakote during pregnancy compared with women who took the newer drug Lamictal.
Death of the fetus, birth defects, and developmental delays, such as walking and speech delays, occurred in 28% of children whose mothers took Depakote compared with just 2% of children whose mothers took Lamictal.
Similar problems were also seen with the use of other seizure medications during pregnancy. Among these other medications, 10% of children whose mothers took Tegretol and 7% of children born to mothers who took Dilantin experienced such problems.
The oldest children in the study are now 2 ½, and researcher Page Pennell, MD, of Atlanta's Emory University School of Medicine, says they need to be followed for several more years to determine if developmental differences persist.
Pennell says most women who take seizure medication for epilepsy need to stay on the drugs during pregnancy because uncontrolled seizures during pregnancy can cause miscarriages.
The conventional wisdom has been that taking seizure medication doubles a woman's risk of having a child with birth defects. But Pennell says it is becoming clear that certain seizure medications carry a higher risk of birth defects than others.
"The evidence against the use of [Depakote] by women during pregnancy is mounting, but the message has not gotten out," Pennell says. "This drug is being increasingly prescribed for other conditions like migraines, bipolar disorder, and mood disorders."
Pennell and colleagues presented data from the five-year study a year early, she says, because the findings were so striking. -->
A spokeswoman for Depakote manufacturer Abbott Laboratories tells WebMD that the fact that only 25 women in the study took the drug could easily have distorted the findings.
"[Depakote] has been around for more than 20 years, and more than 3 million people have been treated," says Laureen Cassidy. "Untreated epilepsy has potentially serious or fatal consequences for both the mother and the child."
More Evidence on Depakote
Another unpublished study also showed a higher rate of problems in children whose mothers took Depakote during pregnancy. This research will be presented in Vancouver this summer at a meeting of birth defect specialists.
Investigators followed 149 women with epilepsy who took Depakote early during their pregnancy and until after they delivered, Diego Wyszynski, MD, PhD, tells WebMD.
Among mothers taking Depakote, 11% had children with birth defects, the most common of which was spina bifida, in which the development of the spinal cord is incomplete. Similar birth defects were seen in 3% of children of women taking all of the other seizure medications studied, and less than 2% among children of a comparison group of women without epilepsy.
Wyszynski says all the women taking Depakote also took either a multivitamin or folic acid supplements during their pregnancies. It is generally recommended that women who are pregnant or might become pregnant take 400 micrograms of folic acid daily to prevent spina bifida, but Wyszynski says women taking Depakote may need 10 times that amount.
"There is no question in my mind that [Depakote] causes birth defects," Wyszynski tells WebMD. "Women who do not have to take it shouldn't, but those who do may be able to decrease their risk by taking higher doses of folic acid."
American Epilepsy Foundation President Daniel Lowenstein, MD, tells WebMD the good news from the Pennell study is the very low rate of problems seen with the newer seizure medication Lamictal. Sixty women in the study took the drug, and problems were seen in just 2% of their children.
"This is some of the earliest data we have seen on this drug, and it is very encouraging," he says. "We have been suspicious for some time that our full appreciation of the potential adverse effects of various anticonvulsive drugs on fetal development has not been completely understood. Studies like this one are exactly what we need to get as close to the truth as we can."