Vaginal microbiota of pregnant women

The vaginal microbiome plays an important role in maintaining the vaginal health of pregnant women. Nevertheless, detailed descriptions of the variations in the vaginal microbiota during pregnancy and cross-vaginal anatomical sites are currently lacking. Our research aimed to fill this void by conducting a cross-sectional study using next-generation sequencing (NGS) technology. Three repeated swabs were collected at the cervix, posterior fornix and lower 1/3 of the genital tract from 34 pregnant Chinese women. A total of 306 vaginal swabs were obtained at the T0 (non-pregnancy),T1 (9±2.6 weeks), T2(18±22.0 weeks), T3(32.3±2.7 weeks) and T4 (postpartum 7±0.3 weeks) trimesters. The bacterial compositions, which were characterized by Illumina sequencing of barcoded 16S rRNA genes, were dominated by members of the Lactobacillus genera for the majority of the samples. The T2 and T3 communities were similar to that for T0, whereas the communities T1 and T4 were significantly different. Repeated samples collected from the cervix, posterior fornix and lower 1/3 of the genital tract presented consistent communities within individuals. For the first time, our study reveals the diversity of the vaginal microbiota during pregnancy and the homogeneity at anatomical sites. In the future, these results may serve as a benchmark for researchers studying vaginal microbiota in pregnant women.