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.
Oophorectomy
Women who have had bilateral oophorectomy surgeries lose most of their ability to produce the hormones estrogen and progesterone, and lose about half of their ability to produce testosterone, and subsequently enter what is known as "surgical menopause" (as opposed to normal menopause, which occurs naturally in women as part of the aging process). In natural menopause the ovaries generally continue to produce low levels of hormones, especially androgens, long after menopause, which may explain why surgical menopause is generally accompanied by a more sudden and severe onset of symptoms than natural menopause, symptoms that may continue until the natural age of menopause. These symptoms are commonly addressed through hormone therapy, utilizing various forms of estrogen, testosterone, progesterone, or a combination.