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
Removal of ovaries causes hormonal changes and symptoms similar to, but generally more severe than, menopause. Women who have had an oophorectomy are usually encouraged to take hormone replacement drugs to prevent other conditions often associated with menopause. Women younger than 45 who have had their ovaries removed face a mortality risk 170% higher than women who have retained their ovaries. Retaining the ovaries when a hysterectomy is performed is associated with better long-term survival. Hormone therapy for women with oophorectomies performed before age 45 improves the long-term outcome and all-cause mortality rates.