Alarelin is a synthetic nonapeptide, a synthetic nonapeptide analog of gonadotropin-releasing hormone (GnRH). Its activity is 15 times that of gonadotropin-releasing hormone (GnRH). It can effectively promote the pituitary gland to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH), reduce estradiol levels, and thus inhibit ovarian function.