Introduction
Vaginitis is the most common infectious disease of female genital tract during childbearing age. Common vaginal infections mainly include BV (Bacterial Vaginosis), AV (Aerobic Vaginitis), VVC (Vulvovaginal Candidiasis), and TV (Trichomoniasis)(1). Mixed vaginitis refers to the infection of two or more pathogens in the vagina at the same time (2). Common mixed vaginitis mainly includes BV+VVC, BV+AV, AV+VVC, TV+AV, TV+BV, TV+VVC, etc. Existing studies have shown that the prevalence of mixed infections during pregnancy is 6.5%-13.2%(3-5), which is higher than that of 2.4%-6.4% in non-pregnant women(6, 7).Low income, low education level, previous vaginal infections, poor personal hygiene, history of antibiotic use, and external hemorrhoids are known risk factors for BV, VVC and AV during pregnancy, but no studies have analyzed the risk factors of pregnant women with mixed vaginitis(5, 8). It is known that single vaginitis during pregnancy, such as AV, BV, and VVC, is associated with the increase in the incidence of PROM (premature rupture of membranes), premature delivery, etc(1, 5). The effect of mixed vaginitis on pregnancy outcome still needs further research. Whether the symptoms, signs and laboratory features of women with mixed vaginitis during late pregnancy are also confused with single vaginitis remains to be studied. Therefore, this study analyzed the mixed vaginitis in late pregnancy to summarize the epidemiological characteristics, risk factors, clinical symptoms and signs, laboratory characteristics, and their impact on adverse pregnancy outcomes in women with mixed vaginitis in the third trimester, so as to provide suggestions for clinical diagnosis and treatment.