Premature ovarian failure — also known as primary ovarian insufficiency — refers to a loss of normal function of your ovaries before age 40. If your ovaries fail, they don't produce normal amounts of the hormone estrogen or release eggs regularly. Infertility is a common result.
Premature ovarian failure is sometimes referred to as premature menopause, but the two conditions aren't exactly the same. Women with premature ovarian failure may have irregular or occasional periods for years and may even become pregnant. Women with premature menopause stop having periods and can't become pregnant.
Restoring estrogen levels in women with premature ovarian failure helps prevent some complications, such as osteoporosis, but infertility is harder to treat.