Various complex decisions are needed to prevent seizures and fetal risks due to exposure to antiepileptic drugs.
At the American Epilepsy Society conference, the North American Commission gave its biannual symposium, Controversies in the Management of Epilepsy During Pregnancy, on Saturday, December 3, 2016.
At this symposium, the speakers discussed the various complex decisions clinicians and their patients must make to prevent seizures, as well as to prevent fetal risks due to exposure to antiepileptic drugs.
Pre-pregnancy planning is important for women with epilepsy. However, because nearly half of pregnancies in the United States are unplanned, it is important for clinicians to discuss this topic early, according to speaker Kimford J. Meador, MD.
Patients should be informed about the fetal risks of antiepileptic drugs as soon as physicians write them a prescription, and should also be reminded of these risks by their pharmacists to ensure that patients avoid potential harm to their fetus.
Fetal malformations are a serious risk for pregnant woman on antiepileptic drugs, especially valproate and phenobarbital. Congenital malformations of fetuses born to mothers taking antiepileptic drugs include heart defects; orofacial clefts; and skeletal, urological, and neural tube defects, according to the session.
Although the risk of delivering a baby with congenital malformations is 2% to 3% in the general population, pregnant women with epilepsy have an increased risk of 4% to 8%.
Dr Meador said that valproate poses a special risk, whereas drugs such as phenobarbital and topiramate pose a lower, intermediate risk of causing congenital malformations. Even at low doses, valproate is associated with decreasing IQ, increasing the risk for autism, and increasing the need for special education services. Neural apoptosis has also been seen in the developing brains of mice that were exposed to certain drugs during gestation.
Although most children born to women with epilepsy do not have these malformations, women must fully understand the risks and take preventive measures to ensure they have taken the necessary steps to plan their pregnancy. Certain contraceptive methods, such as the intrauterine device, offer women an effective and reversible method of preventing pregnancy while taking antiepileptic drugs that may pose harm to a developing fetus.
During his presentation, Dr Meador also said that he gives all his female patients of childbearing age folate prior to becoming pregnant. This was prompted by a study he conducted in which children born to women with epilepsy, who were taking folate prior to becoming pregnant, had 6 higher IQ points compared with children born to women with epilepsy who were not taking folate.
Additional research is needed to better understand the cognitive effects of exposure to antiepileptic drugs before and after birth, because infants may also be exposed to these drugs through breastmilk. There is also a need for more studies that explore the relationship between antiepileptic drugs and the risks of maternal outcomes and that determine the underlying mechanisms that cause some children to develop malformations while others do not, according to the session.
Women with epilepsy must consider many important factors when planning pregnancy. If they are taking a drug that is known to cause congenital malformations, they must discuss their options with their clinicians to ensure their children will not be affected by adverse effects. If clinicians, pharmacists, and women with epilepsy do not discuss the risks associated with antiepileptic drugs, fetuses may be at risk of developing serious conditions.