If the color of menstrual blood is dark green on the first day of menstruation, it is clinically abnormal. Menstruation is vaginal bleeding caused by the shedding of the uterine lining, and the blood is clinically red or becomes coffee-colored when it becomes stale, and it is impossible to change to dark green. If you have dark green menstrual blood, you need to know whether you have used some kind of medication in your vagina before menstruation, such as inserting medication to treat vaginal inflammation or cervical inflammation, and when the medication reacts with the menstrual blood, the color of the menstrual blood becomes dark green, which should be analyzed in conjunction with the comprehensive history of the disease. Under normal circumstances, women’s menstruation is dark red, menstrual blood is non-clotting, there will not be large blood clots in the menstrual blood is normal.