Pathogen profile and risk factors of aerobic vaginitis in pregnant women: a retrospective cohort study

Background: Vaginitis is one of the most common gynecological diseases in women and may severely affect the quality of life in patients. However, very few studies have investigated aerobic vaginitis (AV) in pregnant women, and our study was designed to identify the pathogen profile, clinical importance, and risk factors of AV in pregnancy. Methods: This was a retrospective cohort study enrolling 685 women who attended our hospital between July 2018 and June 2020. Based on the incidence of AV, enrolled women were divided into an AV group and healthy control group, and demographic and clinical characteristics were retrospectively collected by two independent investigators. Some pathogens of AV were tested using quantitative real-time polymerase chain reaction for higher accuracy. Pregnancy outcomes were also retrospectively collected. Univariable and multivariable logistic regression analysis was used to determine the risk factors of AV incidence and adverse pregnant outcomes. Results: Enrolled women were divided into an AV group of 182 women and healthy control group of 503 women. The proportions of women with a history of cesarean delivery and history of vaginal infection differed between the groups (P=0.002 and <0.001, respectively). The mean gestational week at diagnosis of AV was 22.3 +/- 8.6 weeks, and the most common pathogen of AV was Escherichia coli (28.6%). After adjustment using multivariable logistic regression, a history of vaginal infection acted as an important risk factor of AV incidence, while a history of cesarean delivery, college education or above, and being employed could protect pregnant women from AV. In addition, the incidences of preterm birth, premature rupture of membranes, neonatal jaundice, and neonatal infection were much higher in the AV group than in the control group, showing significant difference (P<0.001, <0.001, =0.007, and =0.025). After adjustment using multivariable logistic regression, the incidence of AV and older age were important risk factors of premature rupture of membranes and neonatal infection. Conclusions: Compared with healthy pregnant women, the presence of AV may increase the incidence of adverse outcomes. More attention should be paid to pregnant women with a history of vaginal infection.