Menopause
The menopause transition typically begins between 40 and 50 years of age (average 47.5). The duration of perimenopause may be for up to eight years. Women will often, but not always, start these transitions (perimenopause and menopause) about the same time as their mother did.
Catamenial epilepsy
During menopause, there are drastic changes in the production of gonadal hormones. Most of the reproductive hormones, including the estrogens, progesterone and testosterone, diminish initially (perimenopause), becoming irregular, often showing wide and unpredictable fluctuations. As menopause progresses, there is cessation of estrogen production by the ovaries. Rosciszewska was one of the first researchers to report an increased risk of seizures during perimenopause, but found a marked decreased risk of seizures during menopause if there was a catamenial relationship. This difference may be associated with the radical fluctuations of estradiol and progesterone during the perimenopausal period than what is experienced during the menopausal period and menstrual cycles of reproductive years. Recall that estrone is the predominant estrogen present during menopause (from subcutaneous fat), and little is known about the effect of estrone specifically on epilepsy. Women with epilepsy who do not follow a catamenial pattern may have an unpredictable increase or decrease in seizure activity in perimenopause and menopause, but women with catamenial epilepsy typically follow a more predictable pattern.