The term “period” generally refers to menstruation. Normally, menstrual blood is dark red or red in the middle of the period, and may appear coffee-colored or black on the first and last days of menstruation.
Menstruation is caused by the cyclical growth and peeling of the uterine lining in response to sex hormones produced by the ovaries. Normally menstrual blood is red or dark red in color, but it may appear coffee-colored or black due to the fact that on the first and last days of menstruation, when the menstrual flow is relatively low, the blood stagnates and is oxidized in the vagina.
If a woman finds that the amount and color of her menstrual flow changes significantly during her menstrual period, it may be caused by pathological factors, and it is recommended that she go to the hospital for relevant examinations in a timely manner, and under the guidance of a professional doctor to clarify the cause of the disease, and then carry out targeted treatment.