The black color of menstrual blood with blood clot formation is a manifestation of blood stasis. There are many causes of blood stasis: 1. Qi stagnation and blood stasis is a relatively common type of blood stasis, which occurs due to long-term emotional disorders and depression leading to Qi stagnation, and liver Qi stagnation is the most common one. The blood stasis caused by Qi stagnation affects the discharge of menstrual blood, resulting in black menstrual blood and blood clotting, which can be treated with medicines such as Jia Wei Yi Yuan Wan and Blood Fu Xie Yu Wan. 2. Blood stasis caused by cold clotting is also a common type of blood stasis caused by black menstrual blood and clotting, which is mainly related to cold invasion caused by eating cold food or getting wet. 3.Qi deficiency and blood stasis, caused by various chronic diseases or poor living habits lead to qi deficiency, due to qi deficiency can not move blood leads to blood stasis, thus causing menstrual blood dark color, clots, can be considered to take tonic yang also five soup plus reduction treatment.