Vaginal inflammation is caused by special physiological structure, frequent sexual activities, and low estrogen level after menopause. 1. Special physiological structure: the vulva-vagina is adjacent to the urethra and anus, urine and feces can easily contaminate the local environment of the vagina, coupled with the vagina’s localized humidity, the contaminated area can easily cause bacterial growth, resulting in vaginal inflammation. 2. Frequent sexual activities: women of childbearing age have frequent sexual activities, and the vulva-vagina is the necessary way of labor and delivery, hysteroscopic operation, which makes it easy to be damaged and infected by external pathogens. 3. Low level of estrogen after menopause: low level of estrogen in postmenopausal women and infants and young children, the local resistance decreases, and is also susceptible to infection. When vaginitis occurs, timely consultation and treatment are needed.