Endometrial shedding is a manifestation of the cyclical changes of the ovaries, and is characterized by cyclic shedding and bleeding, which is called menstruation. In general, endometrial shedding is a normal phenomenon. Endometrial shedding can occur as early as 11 years of age and as late as 16 years of age. On average, menstruation occurs around 13-14 years of age, and regular endometrial shedding is often used as an important sign of reproductive maturity. Generally, around the age of 40-50, women’s ovarian function begins to decline and the endometrium no longer shows regular cyclic changes, finally entering menopause. The normal cyclic shedding of the endometrium takes about 2-8 days, with an average of 4-6 days. It may be accompanied by lower abdominal cramps, diarrhea, gastrointestinal dysfunction, headache, back pain and other symptoms, which require attention to warmth, enhanced nutrition and rest. For those who have unbearable pain, they can take pain relieving drugs such as ibuprofen under the guidance of doctors. In addition, abnormal endometrial shedding is often manifested as a change in menstrual cycle, increased or decreased menstrual volume, shortened or prolonged menstrual period, and may also manifest as symptoms such as abnormal vaginal bleeding during non-menstrual periods, which are considered to be related to diseases such as cervical erosion, endometriosis, ovarian cysts, uterine fibroids and endometritis. In addition to affecting menstruation, it may also cause lower abdominal cramps, fever and abnormal vaginal discharge in patients. Patients are advised to go to the hospital in time to improve the examination and actively treat under the guidance of doctors.