What causes the liquid from a woman's vagina to turn black?

I had my period yesterday. I thought it would be bright red like the previous ones, but later I found that the blood turned black, which scared me. Why is menstrual blood black?

Reason 1: Deficiency of Qi and Blood

Deficiency of both Qi and blood in women is also the cause of black menstruation. When deficiency of both Qi and blood occurs, menstruation is usually affected, which can lead to menstrual disorders. Increased or decreased menstrual volume, early or delayed menstruation, prolonged menstruation, lighter color, and thinner menstruation are all manifestations of irregular menstruation. In addition, accompanied by the deficiency of Qi and blood, it will also cause physical abnormalities such as dizziness, pale complexion, sallow complexion, lower abdominal pain, fatigue, limb weakness, and weak pulse.

Reason 2: Kidney deficiency

Kidney deficiency can cause black menstruation in some of our female friends, and the menstrual cycle is often irregular, sometimes coming early, sometimes late, with a small amount of menstruation, light red or dark red in color, and thick menstruation. After kidney deficiency, it will cause soreness in the waist and knees, pain in the heels, and will be accompanied by dizziness and tinnitus, and more urine at night. The tongue is light in color, and the pulse is sometimes weak and sometimes slow. It can be treated by tonifying the kidney and regulating menstruation.

Cause 3 Dysmenorrhea

The main symptom of dysmenorrhea is poor blood circulation, which causes black menstruation and is very unstable. Sometimes it comes early, sometimes late, and the time of occurrence is very irregular. The amount of menstruation is also unstable, sometimes more, sometimes less, and the color is purple-red, with blood clots. Women also have lower abdominal pain, bloating and pain in the breasts, chest and flanks. Observing the tongue, the color of the tongue coating is dark red and has petechiae, or the tongue coating is too white or light yellow. Treatment often uses methods to unblock blood and regulate breath, so as to reduce blood clots and pain.