Used in hormone replacement therapy to relieve symptoms of menopause such as hot flashes, vaginal dryness, and mood changes. Helps prevent bone loss (osteoporosis) in postmenopausal women. Also prescribed for certain cases of estrogen deficiency and to manage symptoms related to menstrual irregularities. Often combined with progestins in women with an intact uterus to reduce the risk of endometrial cancer. Available in oral tablet form for systemic effect.