Vaginal discharge is the fluid secreted by the female reproductive system and is commonly known as “leukorrhea”. It comes mainly from the cervical glands, the vestibular glands, the endometrium and the vaginal mucosa. The cleanliness of vaginal secretions is divided into four degrees: Ⅰ degree A large number of vaginal bacilli and epithelial cells, leukocytes 0-5/HPF (one field of view under high magnification microscope), no or very few miscellaneous bacteria, normal; Ⅱ degree A moderate amount of vaginal bacilli and epithelial cells, leukocytes 10-15/HPF, few miscellaneous bacteria; also normal; Ⅲ degree A small amount of vaginal bacilli and epithelial cells, leukocytes 15-50/HPF, more miscellaneous bacteria, suggesting inflammation; Ⅳ degree No vaginal bacilli, a few epithelial cells, leukocytes few epithelial cells, leukocytes full field of view/HPF, and a large number of miscellaneous bacteria, mostly in severe vaginitis. In the physiological state, the female reproductive system is sufficient to defend against external pathogenic microorganisms due to the histological-anatomical and biochemical characteristics of the vagina. From newborn to adolescence, the labia majora and minora are tightly closed bilaterally, the external female membrane is intact, and the anterior and posterior walls of the vagina are adjoined so that the canal lumen is closed. After shedding, the cells destroy and release glycogen, which is converted into lactic acid by Bacillus vaginalis, keeping the vaginal pH between 4 and 4.5, an environment in which only Bacillus vaginalis can survive. Therefore, in normal healthy women, the vagina itself is self-purifying and forms a natural defense. However, because the vagina is adjacent to the urethra and anus, it is moist and easily contaminated; women of childbearing age are sexually active, and the vagina is a necessary route for childbirth and uterine operations, making it vulnerable to damage and infection by external pathogens. Recurrent vaginitis is often associated with excessive cleaning and treatment. The ecological balance between various microorganisms in the vagina is not pathogenic, but once it is disrupted, the dysbiosis or exogenous pathogens can easily take advantage of the situation and cause inflammation. The common incorrect habits are: 1. daily use of lotion or vaginal douche, pH rise after vaginal irrigation inhibits the growth of lactobacillus from the surface causing other pathogenic bacteria to become dominant, 2. frequent use of sanitary pads, making the perineum hot and humid and not breathable 3. vaginitis taking antibacterial agents at will, causing dysbiosis and serious secondary infection, etc.