As regards the delicate health of the vagina and urinary tract, the Lactobacillus strain is especially beneficial for women suffering from vaginal inflammation – bacterial vaginosis or yeast infections (candidosis). Several studies have concluded that normal vaginal microflora is best restored and maintained by two lactic acid bacteria – Lactobacillus rhamnosus and Lactobacillus reuteri. It has been discovered that these bacteria improve the immune response, reduce the amount of pathogenic bacteria that enters the vagina from the large intestine and inhibit bad bacteria from surviving and forming colonies. 
A double-blind, placebo controlled study by Reid et al found that 32 healthy women displayed a significant increase in the amount of lactic acid bacteria in the vagina after oral supplementation of L.rhamnosus GR-1 and L.fermentum RC-14 bacteria, as compared to the placebo group. The study lasted 2 and 4 weeks. The 64 subjects of the study displayed signs of asymptomatic bacterial vaginosis, but after 2 and 4 weeks of the study their vaginal microflora was rated as normal on the Nugent score. The placebo group displayed significantly less improvements. A similar result was demonstrated in another double-blind study by the same author where 59 subjects were given the same strain of bacteria or a placebo. 
- Reid G. Probiotic Lactobacilli for urogenital health in women. J Clin Gastroenterol. 2008 Sep;42 Suppl 3 Pt 2:S234-6.
- Reid G, Charbonneau D, Erb J, Kochanowski B, Beuerman D, Poehner R, Bruce AW. Oral use of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 significantly alters vaginal flora: randomized, placebo-controlled trial in 64 healthy women. FEMS Immunol Med Microbiol. 2003 Mar 20;35(2):131-4.