Used primarily in hormone replacement therapy to alleviate symptoms of menopause such as hot flashes, vaginal dryness, and mood disturbances. It acts as a synthetic estrogen, helping restore estrogen levels in postmenopausal women. Also utilized in the treatment of certain cases of advanced prostate cancer in men, where suppression of testosterone is beneficial. Topical formulations may address vaginal atrophy and urinary incontinence related to estrogen deficiency. Its use has declined due to the availability of newer estrogens with more favorable safety profiles.