Menopause that happens before age 40 caused by chemotherapy, radiation therapy to the ovaries, surgical removal of the ovaries or failure of the ovaries to make enough of the hormone estrogen.

In premature menopause, the ovaries either have been removed or damaged. Sometimes the ovaries don't make the usual amount of the hormone estrogen. This is called primary ovarian insufficiency.

Symptoms might include infertility, hot flashes, mood changes, sleep problems and vaginal dryness.

Treatment includes hormone therapy at least until the usual age of menopause. Medicine to prevent or treat the bone-thinning disease osteoporosis also might be prescribed.