Preterm Prelabor Rupture of Membranes Linked to Vaginal Bacteriome of Pregnant Females in the Early Second Trimester: a Case-Cohort Design.

Preterm prelabor rupture of membranes (PPROM) is a major cause of spontaneous preterm birth (sPTB), one of the greatest challenges facing obstetrics with complicated pathogenesis. This case-cohort study investigated the association between vaginal bacteriome of singleton pregnant females in the early second trimester and PPROM. The study included 35,255 and 180 pregnant females with PPROM as cases and term-birth without prelabor rupture of membranes (TWPROM) and term prelabor rupture of membranes (TPROM) pregnant females as controls, respectively. Using 16S rRNA sequencing, the vaginal microbiome traits were analyzed. Females with PPROM had higher alpha and beta diversity (P < 0.05) than TWPROM and TPROM. The presence of L. mulieris was associated with a decreased risk of PPROM (adjusted odds ratio [aOR] = 0.35; 95% confidence interval [CI]: 0.17-0.72) compared with TWPROM. Meanwhile, the presence of Megasphaera genus (aOR = 2.27; 95% CI: 1.09-4.70), Faecalibacterium genus (aOR = 3.29; 95% CI: 1.52-7.13), Bifidobacterium genus (aOR = 3.26; 95% CI: 1.47-7.24), Xanthomonadales genus (aOR = 2.76; 95% CI: 1.27-6.01), Gammaproteobacteria class (aOR = 2.36; 95% CI: 1.09-5.14), and Alphaproteobacteria class (aOR = 2.45; 95% CI: 1.14-5.26) was associated with an increased risk of PPROM compared with TWPROM. Our results indicated that the risk of PPROM can decrease with vaginal L. mulieris but increase with high alpha or beta diversity, and several vaginal bacteria in pregnant females may be involved in the occurrence of PPROM.