LAUSR

BACKGROUND Bacterial vaginosis (BV) is a highly prevalent disorder of the cervicovaginal microbiota. Molecular-BV may put women at increased risk for adverse reproductive and obstetric outcomes. We investigated the association of HIV and pregnancy on the vaginal microbiota and associations with molecular-BV in women of reproductive age from Pune, India. SETTING We studied vaginal samples from N=170 women including N=44 non-pregnant HIV seronegative (SN), N=56 pregnant SN, N=47 non-pregnant women with HIV (WWH), and N=23 pregnant WWH, and collected data on clinical, behavioral, and demographic factors. METHODS We used 16S rRNA gene amplicon sequencing to characterize the composition of the vaginal microbiota. We classified the vaginal microbiota of these women into community state types (CSTs) based on bacterial composition and relative abundance, and further categorized them into molecular-BV versus Lactobacillus-dominated states. To determine associations between pregnancy and HIV status with outcome of molecular-BV, logistic regression models were used. RESULTS There was a high prevalence of molecular-BV (30%) in this cohort. We found that pregnancy was associated with decreased odds of molecular-BV (adjusted OR (aOR)=0.35, 95% CI: 0.14-0.87), while HIV was associated with increased odds of molecular-BV (aOR=2.76, 95% CI: 1.33-5.73), even when controlling for multiple relevant factors such as age, number of partners, condom use and douching. CONCLUSION Larger and longitudinal studies are needed to further characterize molecular-BV and the vaginal microbiota in pregnant women and WWH, and relate these factors to infectious, reproductive, and obstetric outcomes. In the long term, these studies may lead to novel microbiota-based therapeutics to improve women's reproductive and obstetric health.