New study finds oral probiotic may support a balanced vaginal microbiome

A recent double-blind and placebo-controlled study sought to investigate the potential benefits of the probiotic strain L. gasseri KABP 064 (CECT 30648) from AB-Biotics and Kaneka Probiotics.¹ Research showed that the probiotic may help support “a balanced vaginal environment” and is able to colonize inside the vaginal tract. The study titled, “Lactobacillus gasseri CECT 30648 shows probiotic characteristics and colonizes the vagina of healthy women after oral administration” was published in August 2025 in the ASM Journal called Microbiology Spectrum.

Data was accumulated over the course of 18 days from 46 healthy premenopausal women between the ages of 18 to 45 years old. The women were split into two groups, 18 women were placed in the probiotic group which received the probiotic strain L. gasseri KABP 064 (CECT 30648) and the remaining 12 women were placed in the control group which received a placebo.¹ The probiotic group was given one capsule daily of either L. gasseri KABP 064 alone, L. gasseri KABP 064 and L. crispatus CECT 30647. Researchers collected vaginal swabs every three days from both groups that were analyzed via quantitative polymerase chain reaction (qPCR) and investigated the two strains.

Data showed that L. crispatus CECT 30647 was not detected at any timepoint. L. gasseri KABP 064 was found to be detectable in 19 out of 34 participants, within the probiotic group. In the placebo group, it was found that one out of 12 participants detected this bacterium.¹ It was reported that 55.9% of participants that were provided the probiotic strain, found L. gasseri KABP 064 detectable within the vaginal tract. Broad-spectrum inhibitory activity was witnessed with several urogenital microorganisms, such as yeast and bacteria.¹

Additionally, researchers reviewed data that highlighted a decrease in non-lactobacilli genera and more beneficial vaginal microbiomes that include Lactobacilli-dominated vaginotypes.

“A healthy vaginal ecosystem is crucial for supporting women’s urogenital health, which can significantly impact women’s day-to-day lives,” comments Marta Pérez, R&D manager at AB-Biotics and lead author of the study.¹ “The administration of probiotics via vaginal tablets or creams has demonstrated efficacy in reducing infection recurrence, however, oral probiotics for vaginal health remains relatively understudied, despite its many advantages, including patient experience and compliance. Probiotic strains for oral consumption must withstand the harsh and diverse environments of the oral-gut-vaginal route. This study aimed to identify strains of vaginal lactobacilli that can resist gastrointestinal conditions and colonize the vaginal tract to support a balanced microbiota.”

The Lactobacillus species has been found to be in large amounts in healthy vaginal microbiomes, as mentioned in the company’s joint press release. Specifically, the press release mentioned L. gasseri and L. crispatus, help “preserve a balanced, acidic pH, inhibiting the growth of pathogens.” This group of bacteria may have potential to help support both urogenital and reproductive health.

“The findings of this research position L. gasseri KABP 064 probiotic strain, marketed as Gyntima Balance outside of the U.S., as a promising probiotic for promoting vaginal health,” Pérez summarized in the press release. “Together with the inhibitory activity demonstrated in vitro, the potential of L. gasseri KABP 064 to colonize and restore the vaginal environment suggests it could effectively support women’s intimate health by reducing the impacts of vaginal microbiome imbalance. We’re excited to continue our research into the potential benefits that Gyntima® Balance can offer women worldwide.”

Reference

1. Perez M, Armengol E, Del Casale A, Campedelli I, Aldea-Perona A, Pérez Otero M, Rodriguez-Palmero M, Espadaler-Mazo J, Huedo P. 2025. Lactobacillus gasseri CECT 30648 shows probiotic characteristics and colonizes the vagina of healthy women after oral administration. Microbiol Spectr 13:e00211-25. https://doi.org/10.1128/spectrum.00211-25