Studies on the effects of probiotic Lactobacillus mixture given orally on vaginal and rectal colonization and on parameters of vaginal health in women with intermediate vaginal flora

Abstract

Objectives: The vaginal microflora is composed of many bacterial species and plays a major role in maintaining the balance of this complex environment. This study was conducted in order to assess the degree and persistence of the colonization of vaginal epithelium by strains from an orally administered mixture of lactobacilli, containing Lactobacillus fermentum 57A, Lactobacillus plantarum 57B and Lactobacillus gasseri 57C. We also monitored its effects on parameters of vaginal health, especially total lactobacilli counts, vaginal pH and Nugent score.

Study design: The patient group in this open study consisted of clinically healthy women with intermediate vaginal flora. Altogether 37 women were included in the study; 25 finished the full cycle consisting of 8 visits during 70 days. Lactobacillus mixture was administered as 1×10(8) c.f.u. once a day for 60 days. Lactobacillus isolates collected from vaginal and rectal samples from studied women during all visits were typed using molecular methods (PFGE for L. fermentum and L. gasseri and MLST for L. plantarum). Total lactobacilli counts, vaginal pH and Nugent score were also determined during the visits.

Results: We confirmed that the ingested strains were able to reach and colonize both sites within the third and eighth visits, i.e. between the 20th and 70th days of the study. Maximal colonization was recorded between the fifth and seventh visits (31st-60th days). Moreover, ingestion of the Lactobacillus mixture was related to normalization of vaginal parameters (within 28-60 days after the initiation of the treatment). This was demonstrated by a decrease of vaginal pH and Nugent score together with an increase of total numbers of lactobacilli in the vagina and rectum. No adverse events were noted during the course of the study.

Conclusions: Oral application of the combination of the three probiotic strains derived from vaginal microbiota of healthy woman with high adherence abilities to both vaginal and colonic epithelium in vitro shows that both individual strains and their mixture can colonize vagina for some weeks, the effect of which is correlated with significant improvement of such parameters like pH and Nugent score values and total numbers of vaginal lactobacilli. This indicates that the mixture may be a good candidate for the planned double-blind, placebo-controlled randomized studies involving larger numbers of women.