What's wrong with less menstrual flow and blackening?

Menstruation volume and blackening are related to a variety of factors, such as emotional instability, or excessive dieting, long-term irregular life, etc. Secondly, there may be a cold caused, when women suffer from uterine cold, there will be less menstrual blackening phenomenon. In addition, as abortion, ring, curettage surgery, etc., also may cause menstrual blood volume reduction blackening phenomenon.