Oral Administration of the Probiotic Lacticaseibacillus rhamnosus CA15 in a Large Cohort of Women with Bacterial Vaginosis and Mixed Vaginitis: Clinical Evidence from a Randomized, Double-Blind, Placebo-Controlled Study

Probiotics represent a valuable approach to boost vaginal health. A randomized double-blind placebo-controlled study was conducted to confirm the health benefits of the orally administered probiotic Lacticaseibacillus rhamnosus CA15 strain in a large cohort of women with bacterial vaginosis and mixed vaginitis, mainly related to mild aerobic vaginitis and vulvovaginal candidiasis. Recruited women were randomly assigned in a 1:1 ratio to receive, for 10 days, oral capsules containing 1 × 1010 colony-forming units of the L. rhamnosus CA15 strain (Active group) or a placebo (Placebo group). Two-hundred women completed this study. Clinical and microbiological parameters were assessed at baseline (T0), 10 days (T1), and 30 days post-treatment (T2). In addition, quality of life was evaluated at T0 and T2. The study protocol was registered on clinicaltrials.gov (ID: NCT05796921). The oral administration of the L. rhamnosus CA15 strain resulted in significant improvements in clinical characteristics of vaginal dysbiosis as well as changes in the vaginal microbiota composition. Furthermore, participants allocated to the Active group reported enhancements in physical and psychological health, social relations, environment, and overall quality of life. No significant changes were observed in the Placebo group. The present study highlights the ability of the L. rhamnosus CA15 to manage vaginal dysbiosis, offering new perspectives for the treatment and prevention of common gynecological disorders.