Gestrinone is primarily used in the treatment of endometriosis, a condition where tissue similar to the lining inside the uterus grows outside it, causing pain and infertility. It works by reducing the production of estrogen and progesterone, which helps to shrink the abnormal tissue and alleviate symptoms such as pelvic pain and menstrual discomfort. Additionally, gestrinone is sometimes prescribed for the management of fibroids, benign tumors in the uterus, by inhibiting their growth. Due to its hormonal effects, it is important to monitor patients for potential side effects, including weight changes, acne, hirsutism, and mood swings. Its use is typically limited to short-term therapy under medical supervision.