Vaginal and amniotic fluid microbiota in women with preterm labor ‒ a comparative microbiological studY
DOI:
https://doi.org/10.15584/ejcem.2026.3.13Keywords:
amniotic fluid, bacterial vaginosis, Gardnerella vaginalis, preterm labor, Ureaplasma spp., vaginal microbiotaAbstract
Introduction and aim. This observational comparative study characterized the vaginal and amniotic fluids of women in preterm labor relative to those who delivered at term. A distinctive feature of this work is the paired, quantitative and culture-based assessment of both the vaginal and the amniotic fluid microbiota, while most previous studies have examined the vaginal compartment alone.
Material and methods. Carried out at a single tertiary center, the study enrolled 120 women in preterm labor at 33–35 weeks of gestation together with 89 women delivering at term (≥38 weeks). Culture-based identification and quantitative analysis were applied to paired vaginal and amniotic fluid specimens.
Results. Preterm labor was accompanied by a reduced prevalence of Lactobacillus spp. and by a markedly higher recovery of Gardnerella vaginalis (60.8%; odds ratio [OR] 12.27, 95% confidence interval [CI] 5.78–26.06) and Ureaplasma spp. (45.8%; OR 9.91, 95% CI 4.23–23.22), exceeding the term group (p<0.001). Higher vaginal pH and polymicrobial associations occurred more often. The amniotic fluid produced microbial growth in 53.3% of preterm cases and vaginal and amniotic detection of Ureaplasma spp. (φ=0.61; p<0.001).
Conclusion. Vaginal dysbiosis showed an association with preterm labor that may be compatible with a contribution from ascending microbial colonization, though causality cannot be inferred from the present data.
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