Menstruation why is black return especially little

Menstruation is the female endometrium in estrogen, progesterone under the joint action, periodic shedding and showing bleeding phenomenon called menstruation, menstrual cycle is generally 28 days to 30 days, menstrual period for 3 days to 7 days, menstrual color is dark red. Menstruation black is also particularly small, to consider whether there is fertilized egg implantation caused by bleeding, at this time to take blood to measure human chorionic gonadotropin in the blood. When ruled out the possibility of pregnancy, consider the hypothalamus-pituitary-ovarian system shows disorder, that is, we often say menstrual disorders, may be due to insufficient estrogen secretion, resulting in less menstruation, color blackening. Or due to endometrial damage caused by uterine adhesions, so that the endometrium can not grow normally, resulting in less menstruation. Show less menstruation, to the hospital in time for examination, clear diagnosis and timely treatment.