Researchers found that the probiotic reduced harmful vaginal bacteria such as Gardnerella and Candida species, while maintaining beneficial microbes like Lactobacillales.
In the gut, participants also showed improved microbial diversity and higher levels of short-chain fatty acid-producing bacteria, supporting a balanced microbiota and overall women’s health.
Study method
These findings were based on a randomised, double‐blind, placebo‐controlled clinical trial conducted in Malaysia.
A total of 112 healthy females (18 to 80 years old) were recruited and randomised to receive either probiotic (n = 58) or placebo (n = 54).
Each sachet contained 1 bn CFU of Lactiplantibacillus plantarum Probio87. Participants were instructed to dissolve one sachet in water and consume it once daily for 12 weeks, likewise for the placebo.
Vaginal and fecal samples were collected at baseline and by the end of the intervention to assess the effects of the probiotics.
All participants had a Nugent score below 7.0 at baseline, which evaluates the presence of bacterial vaginosis (BV) and changes in vaginal microbiota. Scores range from 0 to 10, with a lower score indicating a Lactobacillus-dominated healthy vaginal flora, while a score above 7 represents bacterial vaginosis, a condition resulting from an imbalance in vaginal microflora.
The primary outcome was the change in Nugent score from baseline to week 12 between the probiotic and placebo groups. The secondary outcomes were the changes in vaginal and fecal microbiota composition.
Richer is not necessarily better
After 12 weeks, the placebo group recorded a significantly higher Nugent score compared to the probiotic group, and the probiotic group had a significant reduction in the Nugent score.
While the scores do not reflect a shift in disease status, these findings suggest that Probio87 may contribute to the stabilisation of a Lactobacillus‐dominant environment in the vagina, potentially reducing the risk of dysbiosis over time.
“This supports a preventive, rather than therapeutic, role of the probiotic in healthy women,” researchers wrote.
The secondary outcomes were assessed with the Chao1 and ACE indices. The higher the values, the higher the species richness. At week 12, the placebo group showed significantly higher Chao1 and ACE indices compared to the probiotic group.
While a diverse and balanced vaginal microbiota is generally associated with optimal vaginal health, excessive diversity can indicate microbial imbalance, often linked to infections and disease states.
“Women with BV, for instance, exhibit more diverse and heterogeneous microbial communities with greater species richness and bacterial diversity compared to those without BV,” researchers wrote.
BV is typically characterised by a reduction in the beneficial Lactobacillus species, accompanied by an increase in the pathogenic Gardnerella populations. Patients with BV also report more Cupriavidus and Collinsella aerofaciens.
Crucially, Lactobacillales was not detected in the placebo group, while Gardnerella was not observed in the probiotic group after 12 weeks.
The probiotic also increased the levels of several beneficial bacteria, including Eubacterium, Agathobacter, Ruminococcus, Odoribacter and Dore. These produce short-chain fatty acids that have been found to reduce inflammation and support metabolism and immune health.
Probiotic intervention
Together, the findings suggest that supplementation with L. plantarum Probio87 beneficially modulated both the vaginal and gut microbiota of healthy women.
In addition, no adverse effects or complications were reported during the course of the study.
By targeting a healthy cohort, researchers concluded the trial demonstrated L. plantarum Probio87 “as a promising, safe, and multifunctional probiotic capable of enhancing microbial resilience and promoting eubiosis across gut and vaginal environments, supporting its potential role in the preventive maintenance of female urogenital and gastrointestinal health.”
The study was supported by a grant from Universiti Sains Malaysia (USM) and South Korea’s Probionic Corporation.
Source: Molecular Nutrition & Food Research 2026 Jul 13;70(13):e70535. doi:10.1002/mnfr.70535. “Randomized, Double-Blind, Placebo-Controlled Trial of the Probiotic Lactiplantibacillus plantarum Probio87 for Gut-Vaginal Microbiota Modulation in Healthy Women.” Authors: Azka Ainun Nisaa et al.
