Vaginal microbiota #25

Vaginal microbiome profiles: a potential indicator of preterm birth risk

McKee KS, Bassis CM, Golob J, et al.; ECHO Cohort Consortium. Vaginal microbiome structure in pregnancy and host factors predict preterm birth: Results from the ECHO Cohort.

The vaginal microbiome undergoes changes throughout pregnancy and may help predict the risk of preterm birth. To further investigate this association, researchers analyzed data from 677 pregnant women enrolled in the geographically and demographically diverse U.S. ECHO (Environmental influences on Child Health Outcomes) cohorts, of whom 12% delivered before 37 weeks of gestation.

After adjusting for major maternal factors (including age, ethnicity, education level, and parity), women whose vaginal microbiome was dominated by Lactobacillus crispatus had a lower risk of preterm birth. In contrast, those with a more diverse microbiome (not dominated by lactobacilli) or one predominantly dominated by Lactobacillus iners were at higher risk.

By combining the relative abundance of three key bacterial species (L. crispatus, Gardnerella vaginalis—which is associated with bacterial vaginosis—and Prevotella timonensis) with maternal characteristics, the researchers developed a predictive model with an area under the curve (AUC) of 0.77, a level of performance considered satisfactory by the authors for a clinical prediction tool.

These findings suggest that the vaginal microbiome, when considered alongside maternal factors, could improve obstetric risk stratification and help identify women at increased risk of preterm birth.