A woman's health condition is often reflected in her menstrual cycle, such as the amount and color of her menstrual blood. Many women experience irregular periods, and some even experience dark menstrual blood, which can cause anxiety and fear. So, what exactly causes dark menstrual blood?
1. Why does menstrual blood turn black?
Menstruation is the periodic shedding and bleeding of the uterine lining. Menstrual blood is composed of approximately three-quarters arterial blood and one-quarter venous blood. After leaving the body, the blood coagulates and oxidizes upon contact with air, causing it to darken in color.
When menstrual flow is light and the blood stays in the reproductive tract for a longer period, the hemoglobin and heme in the menstrual blood are fully oxidized, causing the menstrual blood to appear dark. In summary, the color of menstrual blood is also affected by the amount and flow rate of menstruation.
Typically, on the first day of menstruation and towards the end, the bleeding is very light, and the menstrual blood is coffee-colored, dark brown, or black. On the second and third days of menstruation, the bleeding is faster and heavier, so it is often bright red or dark red, and may be accompanied by blood clots.
Therefore, dark menstrual blood does not necessarily indicate anything abnormal. If the duration of menstruation is normal (2-8 days), the total amount of menstrual flow is normal (5-80ml), and the menstrual cycle interval is regular (21-35 days), then the dark menstrual blood is a normal physiological phenomenon and there is no need to be anxious or panicked.
Second, be careful if your menstrual blood is black!
If your menstrual blood is dark throughout your period, or if you notice that your menstrual blood is darker than usual, you should be alert to the possibility of an underlying medical condition. The main possibilities include:
1. Endometrial damage:
Repeated miscarriages, intrauterine surgeries, infections, and other factors can cause partial damage to the endometrium, resulting in the loss of normal cyclical changes. During menstruation, the amount of endometrium shed decreases, leading to reduced bleeding area and menstrual flow. Blood stasis can also cause menstrual blood to appear dark.
2. Intrauterine adhesions, cervical adhesions :
Difficulty in expelling menstrual blood and small amount of blood can lead to dark menstrual blood, often accompanied by dysmenorrhea.
3. Ovarian dysfunction :
When ovarian function declines and estrogen levels are low, the uterine lining cannot proliferate and shed properly, resulting in scanty menstruation. Consequently, the menstrual blood may appear dark or black throughout the menstrual period.
Special reminder: Women of childbearing age who experience abnormal bleeding outside of their menstrual period , especially if the bleeding is dark in color, should definitely go to the hospital to rule out pregnancy-related bleeding, such as threatened miscarriage or ectopic pregnancy .
Dark menstrual blood can be a normal phenomenon, or it can be a sign of abnormality in the female reproductive system.
If the dark color is only at the beginning or end of menstruation, and the menstrual flow and cycle are normal, then everything is fine. However, if you experience a significant decrease in menstrual flow, blood stasis, or difficulty in discharge , please consult a doctor promptly!
