Currently, the drugs used clinically to promote ovulation are mainly used to promote ovulation through the regulation of the hypothalamic-pituitary clomiphene axis. 1. Clomiphene (CC) The most commonly used drug is clomiphene (clomiphene citrate capsule). This drug is an estrogen antagonist that produces a hypoestrogenic effect by binding to pituitary estrogen receptors, inhibiting the negative feedback effect of estrogen on the hypothalamus and stimulating the secretion of pituitary gonadotropins, thus promoting follicular growth. It is mainly used in infertility patients with certain estrogen levels and a sound feedback mechanism in the hypothalamic-pituitary clomiphene axis. 2. Letrozole (LE) Letrozole is an aromatase inhibitor. On the one hand, it can inhibit the conversion of androgens to estrogens, thus weakening the negative feedback effect of estrogens on the hypothalamus and stimulating the secretion of pituitary gonadotropins, thus promoting follicle growth. On the other hand, it can increase the local androgen level of follicles and promote follicle development. Letrozole should not be used in patients with increased androgens in the body. Urotropin (HMG) and recombinant human follicle stimulating hormone (rFSH) Urotropin and recombinant human follicle stimulating hormone are often used to stimulate the ovaries directly and promote follicle growth and maturation. These drugs are often used in patients with hypothalamic and pituitary dysfunctional anovulation, as well as in patients with poor results of clomiphene and letrozole treatment, and are often used clinically in IVF patients to promote superovulation. In addition to the use of drugs to stimulate ovulation, more and more attention is being paid to the improvement of the endocrine environment in ovulation disorders. For example, patients with polycystic ovary syndrome often have hyperandrogenism and hyperinsulinemia. Adjusting the endocrine environment before ovulation promotion in these patients (including Daimler-35, metformin, etc.) can not only achieve satisfactory ovulation rate, but also reduce the abortion rate. In patients with hyperprolactinemia and amenorrhea, bromocriptine is administered to lower the prolactin to the normal range and the patient can resume ovulation on her own, which is also one of the indirect methods of ovulation promotion. Patients with hyper- or hypothyroidism also first adjust endocrine abnormalities before trying to conceive.