Lactobacillus Gasseri for Vaginal Health

Research suggests that Lactobacillus gasseri is one of several Lactobacillus species that naturally colonize the vaginal tract and play a meaningful role in maintaining a healthy vaginal environment, primarily by contributing to acidity, suppressing pathogens, and supporting a Lactobacillus-dominated microbial community. The available evidence — drawn from two randomized controlled trials, multiple laboratory and observational studies, and several reviews — generally supports a beneficial association between L. gasseri and vaginal health outcomes, including potential protection against bacterial vaginosis, yeast infections, and adverse pregnancy-related microbiome changes, though findings are not uniformly positive. A 2023 RCT found that oral L. gasseri supplementation alongside standard antibiotic treatment for bacterial vaginosis did not significantly improve cure rates, though it appeared to support microbiome restoration in women who did respond, while a 2025 RCT demonstrated that a specific strain could travel from the gut to the vagina in roughly half of participants via what researchers describe as an oral-gut-vaginal route, suggesting strain selection matters considerably. Across the broader literature, researchers emphasize that the benefits of L. gasseri are highly strain-specific and may vary by population, hormonal status, and individual microbial context, meaning results from one strain or study population may not generalize widely, and most findings still await confirmation in larger, well-controlled clinical trials.