Randomized, Double-Blind, Placebo-Controlled Trial of the Probiotic Lactiplantibacillus plantarum Probio87 for Gut–Vaginal Microbiota Modulation in Healthy Women

The gut–vaginal axis represents a key frontier in women's health, where probiotics can influence both ecosystems through microbial and metabolic crosstalk. This randomized, double-blind, placebo-controlled clinical trial evaluated the effects of Lactiplantibacillus plantarum Probio87 (9 log CFU/sachet) administered orally for 12 weeks on gut and vaginal microbiota modulation. Healthy women aged 18–80 years without urogenital infections, pregnancy, recent vaginal/hormonal therapies, chronic illness medication, and recent pelvic or gynecological surgery were enrolled. 112 participants were randomized to probiotic (n = 58) or placebo (n = 54). Vaginal and fecal samples collected at baseline and week 12 underwent 16S rRNA sequencing for taxonomic and diversity analyses. No adverse effects were reported throughout the study. Compared with placebo, the probiotic group showed a significantly greater reduction in Nugent score (p = 0.008), indicating improved vaginal health. Microbiota analyses revealed that Probio87 maintained vaginal microbiota by suppressing BV-associated taxa while preserving beneficial Lactobacillales. In the gut, Probio87 enhanced microbial richness and evenness, with notable increases in butyrate-producing genera, indicating a predicted rise in short-chain fatty acid-producing potential and greater ecological resilience. These findings demonstrate that oral supplementation with Probio87 safely promotes balanced gut and vaginal microbiota, supporting eubiosis and integrative female health.