Inclusion Criteria:  Female Diagnosis of focal onset seizures (FOS) i. Established by clinical history and an EEG ii. Patients with a normal EEG may be included if they met other diagnostic criteria based on clinical history Presumably ovulatory women based on menstrual cycles of 21-35 days from beginning of menstrual flow to the beginning of the next menses ≥18-45 years old ≥2 unprovoked seizures per month despite drug trials with ≥1 first-line anti-epileptic drugs (AED) Seizures must show a C1 catamenial pattern in 2 of 3 documented cycles i. C1 pattern will be defined as a two-fold increase in average daily seizure frequency during the menstrual phase, as compared to the follicular and luteal phases of the ovulation cycle, in 2 of 3 documented cycles. The menstrual phase will be defined as days -3 to +3 of the menstrual cycle (where onset of menstruation is defined as day 1) (Herzog et al, 1997). Of note, in the NIH Progesterone Trial, the level of catameniality was 1.69 based on Herzog et al. (1997) criteria though this trial will use a level of 2 to include women only with high levels of perimenstrual catamenial exacerbation. Willingness and ability to comply with scheduled visits and study procedures  Exclusion Criteria:  Progressive neurologic or systemic disorder  Use of systemic hormonal contraception during 3 months prior to enrollment (however, subjects with a progestin-releasing IUD who still have monthly periods may be enrolled)  a. Women on system hormonal contraception will be excluded as these women are not ovulatory  Subject is pregnant or breastfeeding Active suicidal or homicidal ideation Decisionally impaired or comatose individuals.