Ethinylestradiol, also known as ethinylestradiol in clinical practice, is mainly composed of estrogen and can be used in the treatment of patients with reduced estrogen. Commonly used in the treatment of this drug include infertility caused by amenorrhea due to insufficient estrogen secretion, infertility caused by polycystic ovary syndrome, menopausal syndrome, senile vaginitis, endometriosis, pituitary tumors, and hyperandrogenism and other diseases. It is also useful in the treatment of certain specific advanced breast cancers, as well as patients with advanced prostate cancer. As this is a class of sex hormone drugs, it is advisable for patients to choose whether they need to use this drug for treatment, as well as to choose the appropriate dosage for treatment, based on their specific individual conditions.