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Updated: Jul 19, 2026

A Murine Model of Group B Streptococcus Vaginal Colonization
Published on: November 16, 2016
Probiotic Lactobacillus dose required to restore and maintain a normal vaginal flora
G Reid1, D Beuerman, C Heinemann
1H414, Lawson Health Research Institute, University of Western Ontario, London, ON, Canada. gregor@uwo.ca
Abstract:
Forty-two healthy women were randomized to receive one of three encapsulated Lactobacillus rhamnosus GR-1 plus Lactobacillus fermentum RC-14 probiotic dosage regimens or L. rhamnosus GG by mouth each day for 28 days. However, the vaginal flora, assessed by Nugent scoring, was only normal in 40% of the cases, and 14 patients had asymptomatic bacterial vaginosis. Treatment with L. rhamnosus GR-1/L. fermentum RC-14 once and twice daily correlated with a healthy vaginal flora in up to 90% of patients, and 7/11 patients with bacterial vaginosis converted to normal or intermediate scores within 1 month. Ingestion of L. rhamnosus GG failed to have an effect. This study confirms the potential efficacy of orally administered lactobacilli as a non-chemotherapeutic means to restore and maintain a normal urogenital flora, and shows that over 10(8) viable organisms per day is the required dose.
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