Endometrial shedding may be caused by cancer, menstrual cycle, hormone level disorders, endometrial inflammation and so on. 1. Menstrual cycle: endometrial shedding may be caused by the menstrual cycle, because when a woman is menstruating, the endometrial lining of the uterus will change under the dual action of the ovary’s cyclic secretion of progesterone and oestrogen, and the endometrial lining of the uterus will lose the support of progesterone and oestrogen when progesterone and oestrogen are lowered, and thus shedding phenomenon will occur. 2. Hormone disorders: women’s uterine shedding may also be caused by hormone disorders, because if women’s ovarian secretion of progesterone and estrogen is irregular, when there is a disorder, it will lead to women’s uterine lining shedding, and women will also experience menstrual disorders. 3. Inflammation of the uterus: Uterine shedding can also be caused by inflammation of the uterus, because women may have intercourse during menstruation, which leads to infection of pathogenic bacteria directly in the uterine lining of women, and women will develop inflammation, which will lead to endometrial shedding and will affect the recovery of the uterine lining of women. 4. Cancer-induced endometrial shedding: endometrial shedding may also be caused by cancer. If women’s endometrial shedding does not occur during the menstrual cycle, and it is considered as abnormal uterine bleeding, women need to be vigilant against cervical cancer and endometrial cancer. When endometrial shedding occurs, it is recommended to go to the hospital for physical examination in time, and then according to the doctor’s examination result to treat the symptoms.