The main causes of low menstrual flow are the following: a. Blood deficiency. The body blood deficiency or traumatic bleeding, such as postpartum hemorrhage, post-surgical bleeding can cause the body’s Yin and blood deficiency, resulting in a low menstrual blood volume. Second, kidney deficiency. Inherent deficiency of kidney energy, kidney essence or excessive intercourse, excessive childbirth, abortion, etc. damage the kidneys. Third, blood stasis. Women suffer from cold during menstruation, the body is attacked by cold evil, and blood is condensed by cold, which also leads to low menstrual blood. Fourth, phlegm dampness. Many obese women belong to phlegm-damp constitution. In addition, if women find that the amount of menstruation is constantly decreasing, they should go to the hospital for examination and treatment in time to avoid the phenomenon of closed and obstructed menstruation. It is recommended that female patients keep their spirits happy, avoid mental stimulation and emotional fluctuations, maintain an optimistic and confident attitude, eat less sweets and more fresh fruits so that their physical condition will return to normal performance.