The human ovary produces male sex hormones (androgen) and female sex hormones (estrogen). Currently, androgen is not included in hormone replacement therapy for women with premature ovarian failure. Present hormone replacement therapy (HRT) was designed to treat women who experience ovarian failure at menopause (around the age of 50). However, 1% of women will experience premature failure of the ovaries before the age of 40. There have been no studies conducted to determine proper hormone replacement therapies for these younger women. Some research suggests that the usual menopausal hormone replacement therapy is not adequate to protect young women with premature ovarian failure from developing osteoporosis. Women with premature ovarian failure have abnormally low levels of androgens circulating in their blood. This may contribute to the increase risk for osteoporosis.