A variety of bacteria are present in the normal vagina, but they are not pathogenic because of the ecological balance that develops between the vagina and the various flora. Lactobacilli, estrogen and vaginal pH play an important role in maintaining the ecological balance of the vagina. Etiology of vulvovaginal and vaginal inflammation Any factor that can disrupt the ecological balance of the vagina can lead to vulvovaginal and vaginal inflammation. (1) Anatomical basis: the vulva and vagina are adjacent to the urethra and anus and are susceptible to bacterial contamination; in addition, because the perineum is more hidden and locally moist, this provides a suitable environment for the reproduction of pathogenic bacteria. (2) Sexual life: women of childbearing age have more frequent sexual activities and the pH of vagina can be raised to 7.2 and maintained for 6-8 hours after sexual intercourse, which is not only unfavorable to the growth of Lactobacillus but also creates conditions for the growth of pathogenic bacteria. (3) Childbirth: when the fetus and its appendages pass through the birth canal, the tension increases dramatically, causing the birth canal to tear and pathogenic bacteria to enter the wound causing local infection and even systemic symptoms in severe cases. (4) Uterine operation: If the surgical instruments are not strictly sterilized or the operation process is not standardized, pathogenic bacteria can enter and cause medical source infection. (5) Vaginal irrigation: It can break the acidic environment in the vagina, which can lead to the reproduction of pathogenic bacteria. (6) Estrogen: Low estrogen levels in infants and postmenopausal women can reduce local resistance and make infection more likely to occur. (7) antibiotics: long-term application of antibiotics to inhibit the growth of Lactobacillus, so that other pathogenic bacteria become the dominant bacteria. (8) Immunity: Infants and young children, the elderly and those who use immunosuppressants and other groups have low immunity and are prone to infection.