It is difficult to estimate the amount of menstrual flow in 2 hours under normal circumstances. If the total amount of menstrual flow is more than 80 ml during the whole menstrual process, it is clinically diagnosed as excessive menstruation. If the total amount of menstruation exceeds 80ml during the whole menstrual period, it is clinically diagnosed as excessive menstruation. If the amount of menstruation is less than 20ml, it is diagnosed as hypomenorrhea, which can only be estimated by the total amount of menstruation. In addition, under normal circumstances, the menstrual cycle is 28-30 days once, the vast majority of menstruation time is 3-7 days will be clean, and the normal menstrual blood is dark red, there is no blood clots, because the menstrual blood is not coagulated or only a very small blood clots, are all normal phenomena. If large blood clots appear, it is clinically abnormal and it is recommended to go to the hospital for further examination.