If menstruation is regular, in the normal time menstruation came, after rest and no more, just a shorter time than usual, less volume, there may be the following several situations: a. It is recommended to exclude the possibility of pre-miscarriage first, you can use the first urine in the morning to test the early pregnancy test paper, if it is positive it can indicate that it is pregnant. If the test is negative, it is a line, and the volume of menstruation is less than 20ml, which is mainly due to the influence of women’s emotions, environment and pressure, etc. If this is the only time, there is no need to worry too much, women themselves will slowly correct. Second, if the menstrual flow is reduced for more than 3 months, it is recommended to go to the hospital on the second day of menstruation to check the hormone six items to understand the basic hormone level, to see if the abnormal hormone level causes the menstrual flow to be reduced. If the decrease in menstruation continues soon after the abortion, it is recommended that an ultrasound examination be performed to find out if it is due to uterine adhesions.