Epilepsy brings special issues for women, particularly in pregnancy. As the French say, vive la difference. And while equality between the sexes is a goal that most people applaud, the French do have a point.

"Our suspicions have been confirmed: epilepsy affects women differently. Their hormonal and menstrual cycles, pregnancy, menopause—all of those life stages are affected by epilepsy," said Edna Kane-Williams, vice president of programs and services for the Epilepsy Foundation.

Furthermore, Ms. Kane-Williams said, many medical professionals seem to be in the dark. "We've done a professional awareness survey that showed that the physicians these women were seeing weren't aware of the differences," she reported. When women with epilepsy have problems, they are often hormone-based, according to Dr. Mark Yerby, founder of North Pacific Epilepsy Research in Portland, Oregon, and a nationally recognized authority on the subject.

Two specific hormones are especially important: estrogen, which increases the electrical activity of the brain, and progesterone, which has the reverse effect.

"Many women are hormonally sensitive. And so you have these two hormones that act in opposite ways in terms of electrical excitability of the brain. We tend to find that the ratio of estrogen to progesterone in these patients is relatively high, so if we modify this ratio by giving supplemental progesterone, we may be able to improve their seizure control."

Finding the right balance is a key, Dr. Yerby said. "Adjusting the ratio of estrogen and progesterone isn't a substitute for anticonvulsant medication, but hormone supplementation on top of regular seizure medicines really might improve things."

Preparing for pregnancy

Nowhere is the problem more evident—or more complicated—than in pregnancy. In the United States, epilepsy affects nearly one million women of childbearing potential. Alarm bells should go off for women with epilepsy who become pregnant or who are trying to become pregnant. Nevertheless, Dr. Yerby affirms that most women with epilepsy can and do have normal pregnancies.

Some well-documented risks are associated with taking antiepileptic drugs (AEDs) while pregnant, but Dr. Yerby said that the answer usually is not to stop taking the medication.

"Maternal seizures have their own hazards. For instance, what if you had a seizure and fell and injured yourself?" Dr. Yerby asked. He noted that a mother falling on her abdomen could injure the fetus. "In addition, a generalized tonic clonic seizure may actually induce premature labor and a miscarriage," he said.

Women with epilepsy should follow the traditional rules for having a healthy pregnancy. "So much of this sounds like common sense," said Dr. Yerby, "but it's really important. People who have the most successful pregnancies are the people who are healthiest when they're not pregnant."

He recommended that women with epilepsy who are trying to get pregnant should:

• Get their seizures under control
• Find the right medication in the right dose
• Try to get on just one medication
• Take a vitamin supplement containing folic acid
• Avoid smoking
• Be close to normal weight levels
• Eat a sensible and balanced diet

"It's also a good idea for them to talk to their neurologist before they get pregnant so that they understand what the risks are, so they know what they're getting themselves in for."

Specific problems affecting infants

Babies born to mothers with epilepsy face a host of specific problems. Dr. Yerby commented on some of them:

Malformation
"The risk is about twice that for the general population," Dr. Yerby noted. This means that birth defects occur in 4% to 6% of infants born to women with epilepsy. Studies are still being carried out, but he noted that generally the specific kind of medication a woman uses does not seem to affect the malformation rate very much. The most common birth defects include cleft lip and palate and certain types of heart defects.

"I strongly recommend that women with epilepsy have an ultrasound between 16 and 18 weeks into their pregnancy, " Dr. Yerby reported. These diagnostic ultrasounds check for abnormalities with an accuracy rate of over 95%. "I think this is important for family planning, to know whether the child has a birth defect."

Development delay
What I mean by developmental delay is that these children tend to be less likely to learn quickly. The development of language skills in particular tends to be slower." Dr. Yerby notes that this condition affects 2% to 6% of births and differs from retardation in that children with developmental delay sometimes are not permanently impaired, although it's uncertain how many of them catch up.

Hereditary epilepsy
"About 2% of the children whose mothers have epilepsy will have epilepsy." This rate is about double that of the general population, according to Dr. Yerby. He said that having a father with epilepsy does not seem to increase the risk.

Infant mortality
Infants born to mothers with epilepsy are two to three times more likely than others to die soon after birth. "You might say that it's just because they have more birth defects. That explains part of it," Dr. Yerby notes, "but the rates are high right through the first year of life." The reason for the high rate is unclear, but it appears to be related to the mother's seizure control—the more uncontrolled the mother's seizures, the higher the infant mortality rate.

Neonatal internal hemorrhaging
Bleeding once was a major problem in newborn children of mothers with epilepsy, but it has been declining. "We don't see it as much any more, partly because its risk is related to specific AEDs, not all of them," Dr. Yerby notes. He advises pregnant women with epilepsy to take a 10-mg vitamin K supplement each day during the last four weeks before delivery. This has been shown to be helpful in preventing this problem.

Low birth weight
This problem is seen about twice as often in infants of mothers with epilepsy. "It doesn't seem to be related to prematurity."

More good advice

Dr. Yerby strongly encourages all women with epilepsy who become pregnant to have their AED levels monitored regularly. "Because their metabolism changes in pregnancy, their anticonvulsant levels tend to decline. Because of these changes, they become more vulnerable to seizures. About a quarter to a third of women will have more seizures during pregnancy."

He also urges women to work as part of a team with both their obstetrician and their neurologist. "You can't really expect the obstetrician to know how to use anticonvulsant drugs any more than you can expect the neurologist to deliver the baby."

Topic Editor:Steven C. Schachter, M.D.
Last Reviewed:10/23/03