The normal female menstrual cycle is 21-35 days, and the duration of menstruation is usually 2-7 days, with an average of 4-6 days. Menstruation is a physiological condition unique to women. Usually the endometrial shedding starts on the 1st day of menstruation and the amount of menstrual blood is small; on the 2nd and 3rd day the endometrial shedding increases and the amount of menstrual blood increases, the uterus is stimulated to strengthen contraction and then a large amount of menstrual blood is expelled, and later it gradually decreases until the menstrual blood is clean. Normal menstrual blood is dark red in color, and the blood is mixed with shed uterine debris, cervical mucus and vaginal epithelial cells. Under normal circumstances, women of childbearing age need to pay attention when their periods are less than 2 days or more than 8 days, and it is recommended to visit the gynecology department of the hospital for detailed examination to clarify the cause. In addition, women should also pay attention to not having sex, spicy, cold and other stimulating diet, and should not engage in strenuous exercise during menstruation, and should pay attention to regular work and rest, ensure sufficient sleep, and maintain a good state of mind.