What is the reason for the lack of menstrual color black

Women's normal menstrual color is dark red, sticky, no clots, menstruation is black normal refers to the situation of qi stagnation and blood stasis, is the symptoms of irregular menstruation, most of the reasons are caused by endocrine abnormalities, can be in the menstrual period 2-5 days to go to the hospital to draw blood test hormone six, according to the level of hormone secretion, there are targeted hormone treatment, can also be treated with traditional Chinese medicine. If the menstrual volume is small, purple-black, there are blood clots can be oral seven systems of cyperus rotundus pills and motherwort ointment; if menstruation is delayed and accompanied by abdominal pain, can be oral seven systems of cyperus rotundus pills and yuanhu painkillers.