If the leucorrhea increases when the menstruation is approaching, it is often clinically caused by the following reasons: First, due to the change in the hormone level in the body before the menstruation, the endometrial glands secrete vigorously, which leads to an increase in secretions, so the clinical manifestation of leucorrhea increases. However, in this case there are often no other clinical symptoms, such as no vulvar itching, the color of the leucorrhea is not yellow, and there is no odor of secretions and no lower abdominal pain. The second one is caused by vaginal inflammation, which often causes increased vaginal discharge, but often accompanied by vulvar itching or odorous discharge. The third one is caused by pelvic inflammatory disease, which can cause increased vaginal discharge. Therefore, if there is excessive leucorrhea before menstruation, a gynecological examination is recommended to find out if there is pressure and pain in the uterine adnexa and to have routine laboratory tests of the leucorrhea.