A lot of blood with clots during menstruation may be a normal reaction, may also be the emergence of endometritis, need to treat the symptoms, give observation, drug treatment and so on. 1. Normal reaction, some women during menstruation may appear to flow a lot of blood with blood clots symptoms, this situation is generally more normal, if the bleeding is more, the menstrual blood gathered together may appear after the blood clots, generally do not need to be overly nervous, you can drink some warm water, more rest. 2. endometritis, patients with endometritis after the endometrium is stimulated by inflammation may appear this symptom, generally can be used under the guidance of the doctor cefuroxime, amoxicillin and other medications to alleviate the symptoms of blood clots. In addition, for the uterine submucous fibroids, endometrial polyps and other patients may also appear such a situation, need to perform surgery to remove the diseased tissue. It is best not to engage in strenuous exercise during menstruation, and need to maintain a good state of mind.