Low menstrual blood is the most common type of menstrual abnormality. There are many causes of low menstrual blood, which are not exactly the same among different individuals. The common main causes include: 1. Severe anemia can lead to low menstrual flow and the menstrual blood becomes thin and light pink in color. 2. When eating cold food or being stimulated by cold before or during menstruation, resulting in poor discharge of menstrual blood, there will be Too little menstrual blood. This is mainly due to the dark color of menstrual blood and abdominal pain. 3. Hypothyroidism can lead to a decrease in menstrual blood, manifested as scanty menstruation and reduced menstrual flow. 4. Elevated levels of lactogen can also cause a decrease in menstrual flow, accompanied by scanty menstruation or even amenorrhea in severe cases.