Aunt is the common name for menstruation. Menstrual blood with a lot of clots can be seen in pathological causes and physiological causes, such as endocrine disorders. 1. Pathological causes: endocrine disorders, gynecological inflammation or uterine diseases, such as uterine fibroids, submucosal fibroids, endometrial polyps, endometrial thickening or endometrial hyperplasia can cause excessive menstrual clots during menstruation, accompanied by a large amount of menstrual flow. 2. Physiological reasons: under normal circumstances, menstrual blood is not coagulated, generally will not appear too many clots, if the endometrial tissue shedding more or bleeding faster, it may lead to the emergence of blood clots, is generally a normal phenomenon, do not need to worry too much. If there are a lot of blood clots during menstruation, the patient should go to the hospital in time to check whether there are organic lesions, and should not be careless and negligent, so as not to cause adverse consequences.