Chlorotrianisene is a synthetic estrogen primarily used in the field of medicine for hormone therapy. It treats symptoms associated with menopause, such as hot flashes, night sweats, vaginal dryness, and osteoporosis. It has been employed in the management of estrogen-dependent breast cancer in postmenopausal women to control cancer cell growth. In men, it has been used to treat prostate cancer by reducing testosterone levels that fuel cancerous cells. Historically, it was also used to prevent miscarriage in women with a history of repeated abortions. Its estrogenic properties address hormonal imbalances or deficiencies. However, its use has declined due to newer, more targeted therapies with fewer side effects.