Catamenial seizures are associated with a woman’s menstrual cycle. For more than 100 years, the relationship between seizures and menstruation has been examined. Studies have shown that fluctuations in female hormones prior to and during menstruation may elevate seizure frequency in some women.

In a small percentage of women, catamenial seizures may occur only during the days just before their periods; for others, during the period itself. Higher ratios of estrogen to progesterone may increase seizure frequency. Water retention, electrolyte imbalance, and even poor sleep are also contributing causes.

The connection between menstruation and seizures has been demonstrated in women with simple partial, complex partial, and generalized tonic-clonic seizures. However, different types of seizures may be associated with different phases of a woman’s menstrual cycle.

For example, a woman with absence seizures may have more seizures during days 16 to 28 of her average cycle, and may have the least during her period. A woman with partial seizures, on the other hand, tends to have fewer seizures during days 16 to 28 and more just prior to ovulation and during menstruation.

Women with epilepsy have reported menstrual disorders, such as amenorrhea (the absence of menstruation), oligomenorrhea (a scanty menstruation), cycles of irregular length and an absence of changes in cervical mucus. This is especially the case for those who experience complex partial seizures.

Anticonvulsant medication may further aggravate mood swings, often pronounced prior to and during menstruation. If mood swings become problematic, it is recommended you discuss adjustments to medication with your physician and/or neurologist.