Estradiol (es tra DYE ole) reduces the number and severity of hot flashes due to menopause. It may also help relieve the symptoms of menopause, such as vaginal irritation, dryness, or pain during sex. It can be used to prevent osteoporosis after menopause. It is also used to reduce the symptoms of late-stage breast or prostate cancer. It works by increasing levels of the hormone estrogen in the body.