A: Dr. Kimford Meador advises
A woman with epilepsy who wants to become pregnant is between a rock and a hard place. You have to balance seizure control with the risk of exposing the unborn baby to a drug.
Women may feel that it's safer to stop taking their drugs. That's not a good idea. In fact, one survey showed that the rate of death in pregnant women with epilepsy was ten times that of pregnant women in the general population. That increase was mostly due to women cutting back or completely stopping their drugs because they feared the medication might hurt their babies. But then some of the women had seizures and died.
That study also showed that there was a greater risk of an impact on their baby's mental abilities when the woman had more than five generalized convulsions during pregnancy. (These are sometimes called “grand mal” convulsions. In this type of convulsion, people usually black out, fall to the ground, and shake all over.)
Although some women with very mild epilepsy can be taken off their medications, the majority will have to keep taking their medications. Most babies born to women who are taking epilepsy medications are born healthy. But the medications do raise the risk of some serious adverse side effects.
Thus far, no medication has been shown to be completely safe for the unborn baby, but some are more worrisome than others. Several recent studies show that Valproate (Depakote, Depacon, Depakene) is more likely to be associated with serious adverse outcomes, including miscarriage, major birth defects, and slow development. For example, about one in four of the children born to mothers who took valproate had a serious problem, compared to one in 10 born to mothers took other epilepsy medications. My personal opinion is that valproate shouldn't be used as a first-line drug for women of childbearing age. Still, there are cases in which it must be used because it works best.
Talk to Your Doctor First
It's best to talk to your physician before you become pregnant since you don't have much leeway to change medications afterwards. Unfortunately, most of the time, women are well into the first trimester before they find out they are pregnant. A lot of the major birth defects have already occurred by this point.
If you're planning on becoming pregnant and you are taking multiple medications, your physician will want to try to get your seizures under control with a single drug. That's because the risk of birth defects is greater when women are on more than one medication. Several medications do look better in research on animals. At this point we can say that lamotrigine (Lamictal) is looking pretty good.
Reduce Other Risk Factors
We advise that women reduce their other risk factors, such as smoking and alcohol consumption.
Your physician is also likely to suggest you take a folate supplement, as some of the medications appear to interfere with folate, which is important to fetal development. Because certain medications interfere with vitamin K, your physician may also suggest that you take supplements and that your baby get a vitamin K injection immediately after birth to prevent brain hemorrhage.
We also recommend that women with epilepsy get early pregnancy blood screening and high-grade fetal ultrasound. These two tests can diagnose more than 95 percent of the major congenital malformations. If the results are negative, then she has one less thing to worry about during her pregnancy; if they are positive, she can prepare. Studies have shown that parents who know about a problem beforehand deal with it better.
One way to help researchers get a better handle on which medications are safer is for women to sign up in one of the pregnancy registries. There is one called the Antiepileptic Drug Pregnancy Registry that includes women from North America (www.mgh.harvard.edu/aed/).
Kimford Meador, M.D.
Greer Professor of Neurology at the University of Florida in Gainesville