According to estimates, there are approximately 500,000 women with epilepsy who are of childbearing age in the United States, and three to five births per thousand will be to this population.1 Though most patients with epilepsy have well-controlled seizures, times of pregnancy require special vigilance in managing the condition in order to keep both mother and child safe.
“The risk of negative pregnancy outcomes is increased for both woman and child, but the vast majority of women with epilepsy are capable of having a healthy pregnancy,” Kimford J. Meador, MD, professor of neurology and neurosciences at Stanford University, and clinical director of the Stanford Comprehensive Epilepsy Center, told Neurology Advisor. This is important to emphasize, he says, considering that, not long ago, many states legally prohibited people with epilepsy from getting married – and some allowed for their sterilization — due to misconceptions about the nature of the condition and associated risks. The last of these laws was repealed just 35 years ago.2
Epilepsy Management: Before Pregnancy
Ideally, the topic of pregnancy should be discussed with women of childbearing age well before conception. “These issues should not be addressed for the first time when the woman becomes pregnant,” said Dr. Meador. “Any physician working with women of childbearing age with epilepsy needs to discuss” the circumstance with them in advance.
This will help not only once the woman becomes pregnant, but also with family planning efforts. Some antiepileptic drugs (AEDs) can interfere with birth control pills, for example, and vice versa. From the obstetrics perspective, Thomas McElrath, MD, an obstetrician at Brigham and Women’s Hospital and an associate professor of obstetrics at Harvard Medical School, told Neurology Advisor that he enjoys treating this population because they tend to be particularly responsible and proactive about their care. “They come to all appointments, they’re very medically savvy, and appreciate what you’re trying to do for them.”
If the patient’s epilepsy is well-controlled approximately 9 months before pregnancy, it is likely to remain so during pregnancy.1 Prior to conception, AED options should be explored with advance consideration for the effects of each in the case of pregnancy, with the goal of choosing the most effective AED with the lowest risk. Some AEDs are associated with birth defects – especially valproate, which has been shown to confer a 10% risk of major congenital malformation3 and is typically no longer used in pregnant women. It has also been found to increase the risk of autism and to reduce IQ, memory, language capacity, and executive function in children whose mothers took it during pregnancy. The effects of certain AEDs are similar to those of fetal alcohol syndrome. “They cause nerve cells to die, and the remaining cells don’t work right,” explained Dr. Meador, who co-authored a review of the risks of various AEDs for pregnant women with epilepsy.3
Medications with intermediate risk include topiramate and phenobarbital, though some research shows that the latter drug may interfere with the child’s cognitive abilities, Dr. Meador said. Two drugs associated with the lowest level of risk are lamotrigine and levetiracetam,3,4 which treat a broad spectrum of epileptic disorders.
“In our ongoing studies, these are the ones being used in epilepsy centers the most in the U.S. right now,” Dr. Meador said. Carbamazepine is also in the low-risk category, and others that appear to have a lower risk are oxcarbazepine and zonisamide.
When considering which medication is most appropriate for a patient, he starts with the lowest-risk option. “If I start a woman on valproate first and the baby ends up with a malformation, I can’t fix that, but if I prescribe a drug and it doesn’t work I can fix that.”