Description: According to Andrew Herzog, M.D., MSc, Director of the Harvard Neuroendocrine Unit, Beth Israel Deaconess Medical Center, Boston, MA, the idea of a relationship between seizure frequency and a woman’s menstrual cycle, known as catamenial epilepsy, dates back more than a century to Sir William Richard Gowers, an eminent British neurologist who wrote a textbook considered at the time to be ‘The Bible of Neurology’. Herzog’s presentation at the 58th Annual Meeting of the American Academy of Neurology, San Diego, further characterizes the relationship between seizures and a woman’s menstrual cycle.