Natural menopause happens when your ovaries develop and release their last follicle and egg and stop producing estrogen. Medically induced, or treatment induced, menopause happens when there is surgical removal of both ovaries (oophorectomy). Medical menopause occurs also when a severe medical issue like breast or uterine cancer has been treated or managed with chemotherapy, radiation therapy, and/or hormonal therapy.
A hysterectomy, which is the removal of the uterus, does not necessarily mean menopause – it depends if one or both ovaries were removed at the same time. However, women who undergo a hysterectomy to treat fibroids or excessive bleeding have a nearly two-fold increased risk for developing menopause early.