In the days before menstruation, there will be leukorrhea, and the amount of leukorrhea will increase, mainly because the endometrial gland secretion is more vigorous before menstruation, so it will lead to leukorrhea begin to increase, but the increase in leukorrhea will not change in nature, only in the amount of increase, the color is still milky white, there is no odor, or only a faint fishy smell, which is a normal phenomenon. However, if the following situations occur, it is an abnormal phenomenon: First, the color becomes yellow. Second, burning sensation or uncomfortable feeling in the vagina. Third, accompanied by vulvar itching. Fourth, leukorrhea with blood. All of the above are abnormal phenomena, it is recommended that the best clinical gynecological examination to understand whether there is inflammation of the vagina and cervix, if necessary, to do a high magnification of the routine examination of leukorrhea, and then give treatment.