Aunt usually refers to menstruation, menstruation with a lot of blood clots may be a normal physiological phenomenon, or may be caused by submucosal fibroids, adenomyosis and other pathological factors. 1. Physiological reasons If there are a lot of blood clots discharged during menstruation, the first consideration is that the thickened uterine lining is discharged from the body under the action of hormones. If there are no other uncomfortable symptoms, it is enough to keep warm during menstruation. 2. Pathologic causes (1) Submucous fibroid: it will make the uterus larger, and the typical clinical symptoms are heavy menstruation and blood clots during menstruation. (2) Adenomyosis: it means that the endometrium is trapped in the myometrium due to some reasons, and the myometrium is interspersed with endometrium, so every time you have a period, this part of the endometrium will also be shed and bleed, and the amount of menstruation will be significantly increased and there will be blood clots. Blood clots during menstruation may also be related to other factors, it is recommended to go to the hospital in time for relevant examinations to clarify the cause of the disease and symptomatic treatment.