Epilepsy in Women -- American Family Physician

Hormones and Seizures Ovarian steroid hormones alter excitability of neurons of the central nervous system. Estrogen reduces inhibition at the gammaaminobutyric acid (GABA-A) receptor, enhances excitation at the glutamate receptor, and increases the number of excitatory neuronal synapses. Progesterone enhances GABAmediated inhibition, increases GABA synthesis, and increases the number of GABA-A receptors. In animal models of epilepsy, estrogen increases and progesterone decreases the likelihood that a seizure will occur. Women with epilepsy may experience changes in seizures at puberty, during the menstrual cycle, and at menopause. These seizure patterns are believed to be associated with changes in estrogen and progesterone levels. Although some epilepsy syndromes, such as childhood absence (petit mal) and benign partial epilepsy with centrotemporal spikes (rolandic epilepsy), usually remit at puberty, other epilepsies worsen, especially those that involve partial seizures. Juvenile myoclonic epilepsy is a common epilepsy syndrome occurring primarily in women at puberty and characterized by absence, myoclonic, and tonic-clonic seizures. Juvenile absence epilepsy, characterized by absence E pilepsy is a group of neurologic conditions characterized by recurrent unprovoked seizures.Approximately 1 percent of the population has epilepsy, making this one of the most common chronic health conditions affecting reproductive-aged women. While the prevalence of epilepsy and approach to treatment are similar for men and women, women with epilepsy are more likely to experience seizure patterns that relate to reproductive cycles and are at risk of reproductive health dysfunction and pregnancy complications. The ovarian steroid hormones estrogen and progesterone alter neuronal excitability and affect the seizure threshold. Epilepsy and antiepileptic drug-related changes in hypothalamic, pituitary, and gonadal hormones have been associated with increased rates of infertility, anovulatory cycles, menstrual irregularity, and polycystic ovaries. Children who are born to women with epilepsy have a higher risk of birth defects, probably related to inutero exposure to antiepileptic drugs. These hormone-seizure interactions and reproducEpilepsy in women raises special reproductive and general health concerns. Seizure frequency and severity may change at puberty, over the menstrual cycle, with pregnancy, and at menopause. Estrogen is known to increase the risk of seizures, while progesterone has an inhibitory effect. Many antiepileptic drugs induce liver enzymes and decrease oral contraceptive efficacy. Women with epilepsy also have lower fertility rates and are more likely to have anovulatory menstrual cycles, polycystic ovaries, and sexual dysfunction. Irregular menstrual cycles, hirsutism, acne, and obesity should prompt an evaluation for reproductive dysfunction. Children who are born to women with epilepsy are at greater risk of birth defects, in part related to maternal use of antiepileptic drugs. This risk is reduced by using a single antiepileptic drug at the lowest effective dose and by providing preconceptional folic acid supplementation. Breastfeeding is generally thought to be safe for women using antiepileptic medications. (Am Fam Physician 2002;66:1489-94. Copyright© 2002 American Academy of Family Physicians.)