Most of the lumps that come out during menstruation are considered to be shed endometrial lining mixed with cervical mucus, and to a lesser extent, pregnancy tissue. Generally, menstrual blood is dark red in color, and in addition to blood, there are endometrial debris, cervical mucus and vaginal epithelial cells. Mixed together, if when the endometrium shed more, mixed with menstrual blood, then it is easy to form a pile of things, if the amount of outflow is not large, then consider it a normal physiological phenomenon, generally do not need special treatment. Of course, if a woman of childbearing age, there has been a short period of menopause, then it can not be ruled out that the flow out of the pregnancy tissue, which generally represents a natural abortion or biochemical pregnancy. Therefore, if there is something abnormal outflow during menstruation, it needs to be analyzed in conjunction with the menstrual cycle, the size of the amount of comprehensive analysis, if there is any abnormality, it is recommended to consult a doctor in a timely manner, so as to avoid delaying the condition.