A routine white belt test pH of 4.4 is normal. The normal vaginal pH is 3.8-4.4, which is weakly acidic to prevent pathogenic bacteria from multiplying in the vagina. Normally, a variety of microorganisms are present in the normal vagina, but these microorganisms and the host vagina are interdependent and regulated by estrogen, local pH, lactobacilli and the immune system of the vaginal mucosa to achieve a dynamic ecological balance that is not pathogenic. If the vaginal micro-ecological balance is disturbed, it may lead to vaginal infections. The acidic environment of the vagina is altered, such as frequent sexual intercourse and vaginal irrigation, which can increase vaginal pH, which is not favorable for the growth of Lactobacillus and favors the growth of anaerobic bacteria, leading to bacterial vaginosis. In addition, long-term application of broad-spectrum antibiotics can inhibit the growth of Lactobacillus and lead to excessive proliferation of fungi, causing vulvovaginal pseudomonal yeast disease or exogenous pathogens such as Trichomonas vaginalis invasion, which can lead to trichomoniasis. In addition, patients are advised to maintain personal hygiene in daily life, change underwear regularly and keep the perineum clean and dry.