Anti-Mullerian duct hormone (AMH) is a dimeric glycoprotein. In women, AMH is secreted only by the ovaries and is produced by the antral follicles and small sinus follicles, which are the earliest follicle-producing substances detectable in peripheral blood, and its main physiological function is to inhibit the development of the Mullerian ducts during gonadal differentiation. Serum AMH levels are not affected by the menstrual cycle or exogenous hormones, but are closely related to the number of sinus follicles and reproductive age. I. AMH and female fertility assessment The predictors of ovarian reserve function are age, number of small follicles in the ovary, FSH level and inhibin-B concentration in the blood 2-4 days after menarche, and AMH. Many studies have now demonstrated that AMH can assess ovarian reserve function earlier and more accurately. Since AMH is produced by the granulosa cells of the antral follicles and small sinus follicles, the higher the number of small follicles in the ovary, the higher the serum AMH value, and conversely, the lower the number of small follicles in the ovary, the lower the serum AMH value. Measurement of AMH levels can give a relatively true picture of the primordial follicle inventory. In contrast, a woman’s age cannot be an absolute indicator of ovarian reserve. In some younger women, their ovarian reserve function decreases, as evidenced by lower serum AMH values, meaning that actual age is not equal to ovarian biological age. With age, serum AMH levels appear earlier than changes in hormone levels such as FSH in women with normal ovulation. Studies have found that serum basal AMH levels between 0. 5 and 1. 1 ng/ml are indicative of a decrease in ovarian reserve. When the quality and quantity of eggs in the ovaries of adult women decreases and decreases, it indicates that the ovaries are aging and that female fertility is in progressive decline. Therefore, AMH is the most sensitive early indicator to assess ovarian reserve function. In vitro fertilization-embryo transfer (IVF-ET), the selection of controlled ovarian stimulation regimen and the dose of ovarian stimulation drugs are important to ensure the success of the procedure, and the assessment of ovarian reserve function and prediction of ovarian responsiveness to drugs is the first step. AMH serum levels are positively correlated with the number of sinus follicles and are involved in the recruitment of sinus follicles. Many studies have shown that AMH is a more sensitive and accurate predictor of ovarian responsiveness than traditional markers, and that AMH provides a more objective assessment of ovarian responsiveness. When the AMH value is below 0.5 ng/ml, it means that the ovaries are less responsive to exogenous gonadotropins, fewer oocytes are recovered after drug stimulation of the ovaries, corresponding to fewer fertilized eggs and fewer embryos available for transfer, thus affecting the pregnancy rate. The incidence of ovarian hyporesponsiveness during the IVF process is about 10%, and the success rate of IVF decreases dramatically in those with low ovarian response. As ovarian reserve gradually decreases with age, the responsiveness to pro-ovulatory drugs decreases and there are significant individual differences in the rate of decline. On the other hand, when the AMH value increases, it means that the ovaries are highly responsive to the pro-ovulatory drugs and are prone to ovarian hyperstimulation (OHSS), which can lead to more serious complications and endanger the health and life of the patient. In particular, the risk of OHSS is greater when the AMH value is greater than 10ng/ml. The determination of AMH value before IVF promotion to understand the responsiveness of ovaries to ovulatory drugs can guide us to rationalize and individualize the selection of ovulatory regimen and the dose of ovulatory drugs, thus the financial burden of patients, reduce the occurrence of OHSS, and improve the success rate of IVF on the basis of ensuring patient safety. Therefore, AMH is an important guide in predicting ovarian follicle inventory, female fertility and ovarian responsiveness to ovulation-promoting drugs. For young women, testing AMH levels to assess ovarian function can avoid missing the optimal age of fertility and reduce the occurrence of ovarian hyperstimulation in IVF; for infertile women of advanced age, testing AMH levels to understand ovarian responsiveness to drugs can guide the rational use of ovulation-promoting drugs during IVF, thus reducing the financial burden on infertile patients.