The following three conditions are mainly considered: 1, the patient may have pelvic inflammatory disease, endometritis and other gynecological diseases, because by the influence of these gynecological diseases, the discharge of menstrual blood is also affected, so that the menstrual blood becomes a piece of the uterine cavity under the action of inflammatory secretion, and the color of the blood clots in the late stage will become black. 2, if the patient is in the period of menstruation or before menstruation, to eat too cold or cold food, or in the period and before menstruation by the external cold stimulation, both of which will affect the normal discharge of menstruation, and therefore make the menstrual lumps and the phenomenon of blackening. 3, if the patient in the period or before menstruation, eating too much cold or cold If the patient eats too cold or too cold food during or before menstruation, or is stimulated by the cold outside during or before menstruation, these two aspects will affect the normal discharge of menstruation, which will make the menstruation clumps and darken the color of the blood clots. 3. Before and after the menstruation period of a woman, because of spicy and stimulating food, or do not pay attention to the maintenance of their own body, body is too fatigued or emotionally unstable, it also leads to the occurrence of such a situation.