In the ART cycle, the correct evaluation of ovarian reserve capacity and its responsiveness to controlled ovulation will help the doctor to develop a reasonable ovulation promotion plan, and ANH is one of the indicators used to evaluate the reserve capacity of the ovaries. 1. What is AMH Anti Müllerian hormone (AMH) is a glycoprotein that is a member of the transforming factor-β superfamily. During early mammalian embryonic development, AMH is secreted by testicular support cells and can inhibit the development of the Müllerian ducts, which gradually degenerate and participate in fetal gonadal differentiation (and is not a determinant of fetal sex). In males, in the presence of AMH, the Mullerian ducts degenerate and the mesonephric ducts evolve into male reproductive ducts. In the absence of AMH, the Mullerian ducts persist and cause male pseudohermaphroditism; in females, the Mullerian ducts evolve into female reproductive ducts and the mesonephric ducts degenerate. The number and quality of primordial follicles at birth determines the ovarian reserve, and the development of these primordial follicles is arrested at the first meiotic stage until puberty when they are recruited and begin to secrete AMH. In reproductive-age females, AMH is produced by the granulosa cells of the recruited antral follicles and small sinus follicles, which bind to AMH receptors on the surface of the adjacent follicular granulosa cells via the paracrine pathway, inhibiting the initial production of primordial follicles. It inhibits the initial recruitment of primordial follicles and reduces the depletion of primordial follicles. In patients with premature ovarian failure, antral follicles, especially granulosa cells, are defective, resulting in lower AMH levels, which in turn accelerate the recruitment and depletion of primordial follicles, thus entering a vicious cycle. AMH remains relatively constant during the menstrual cycle, is negatively correlated with age, and is currently the most effective and sensitive indicator for assessing ovarian function and reserve capacity. The clinical assessment of ovarian function requires a combination of AMH, age, AFC and sex hormones, and the AMH varies widely among women.