What is the reason why the aunt's quantity is very small and the color is not right

Female menstruation when the menstrual flow is very small, at the same time the color is not right, the reason is more, such as women in abortion surgery after showing this situation, there may be due to abortion surgery damage endometrial muscle layer, resulting in too thin endometrium caused by menstrual flow too little, but also may be abortion surgery after uterine adhesion caused by menstrual flow reduced. If a woman's menstrual flow is low and the color is not right every time she menstruates, it may be due to decreased ovarian function or abnormal performance caused by polycystic ovary syndrome. If a woman's menstrual flow is normal, suddenly showing low menstrual flow may be abnormal bleeding caused by pregnancy.