Menstrual cycle hormones influence seizure frequency

Monthly hormone cycle changes

Researchers are exploring how hormone levels impact certain brain activity during the menstrual cycle and the results may influence how birth control pills doses are prescribed to women with conditions like epilepsy in the future.

Increased levels of certain reproductive steroids correspond to more frequent generalized tonic-clonic seizures (GTCS) in women with epilepsy, according to new research from Beth Israel Deaconess Medical Center in Boston.

Scientists found that female epilepsy patients had 30 percent more GTCS a day during anovulatory cycles (menstrual cycles where an egg is not released) than during ovulatory cycles. Previous research has shown that anovulatory cycles are associated with higher levels of the sex hormones estradiol and progesterone.

Study author Andrew Herzog and colleagues analyzed data from the three-month Progesterone Trial Study, which investigated the use of progesterone therapy for focal onset seizures. Of the 281 women who participated in the study, 92 had both ovulatory and anovulatory cycles during the study. Only the daily frequency of GTCS, and not that of complex partial seizures or simple partial seizures, increased significantly during anovulatory cycles.

Other studies have shown that women with epilepsy are more likely to have anovulatory cycles than women who don’t have epilepsy. The research was published July 14 in the journal Epilepsia.