Endometrial shedding is the material formed by the shedding of the endometrium of a woman’s uterus, which is an important part of her menstrual bleeding. The uterus is composed of the muscular layer of the uterus and the endometrium, and the endometrium is shed regularly along with a woman’s physiological cycle. When the endometrium is shed, it forms a woman’s menstruation. If there is a problem with the endometrium, you need to know whether the thickness of the endometrium is normal in conjunction with your own physiological cycle, and the cyclical nature of the endometrium, which changes periodically at different times. The endometrium is at its thinnest when the period has just ended, at around 3mm. When a woman enters ovulation, the endometrium appears to thicken to a certain extent and can reach around 8mm. When a woman reaches premenstruation, the thickness of the endometrium reaches about 1.1mm.