At menopause, a woman’s body makes less estrogen and she stops having menstrual periods. This is a natural stage in a woman’s life. The lack of estrogen can bring on symptoms such as hot flushes and vaginal dryness. It also can increase the risk of osteoporosis (bone loss). Because of this, women may choose to take hormone therapy after menopause. The amount of estrogen produced by the ovaries decreases as a woman ages. At some point, the ovaries stop making enough estrogen to thicken the uterine lining. This is when the menstrual periods stop and menopause occurs. The average age when a woman has her last menstrual period is 51 years, but the normal range is from ages 45 to 55 years. If a woman’s ovaries are removed during surgery, her estrogen level will decrease suddenly. In most women, this brings on symptoms of menopause. Women can take hormones to relieve symptoms of menopause.