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The UREX™ probiotic blend may support urogenital health

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7 Min read

Bacterial imbalances in the vaginal and urinary tracts can be associated with the development of bacterial vaginosis, yeast infections and urinary tract infections. These conditions are very common and can challenge well-being. In clinical trials, participants who consumed the UREXTM probiotic blend (a specific blend of Lactobacillus rhamnosus, GR-1® and Lactobacillus reuteri, RC-14®, hereafter referred to by use of their trademarks GR-1®, RC-14® and UREXTM) experienced improvement of symptoms and a reduction in the incidence of urogenital infections.1, 2, 3, 4 

  • 12-50% of women worldwide experience vaginal infections, which can be caused by bacterial imbalances.5, 6, 7

  • 50-75% experience vaginal infections due to yeast8, 9 and 150 million people are affected by urinary tract infections each year.10

Clinical studies suggest:

Probiotics support bacterial balance in the vagina:

Strain: Lactobacillus rhamnosus, GR-1® and Lactobacillus reuteri, RC-14®1, 11
Potency: 1-2 billion CFU/day*1, 11

2-6 weeks*1, 11

* depending on level of bacterial imbalance and woman’s age

Probiotics combined with an antibiotic course support bacterial balance:

Strain: Lactobacillus rhamnosus, GR-1® and Lactobacillus reuteri, RC-14®3, 12
Potency: 2 billion CFU/day3, 12
Duration: 4 weeks3, 12

Probiotics combined with an antifungal course support a balanced environment and reduce the presence of yeast:

Strain: Lactobacillus rhamnosus, GR-1® and Lactobacillus reuteri, RC-14®4
Potency: 2 billion CFU/day4
Duration: 4 weeks4

Probiotics support bacterial balance and reduce the incidence of urinary tract infections:

Strain: Lactobacillus rhamnosus, GR-1® and Lactobacillus reuteri, RC-14®2
Potency: 2 billion CFU/day2
Duration: 1 year2

Bacterial balance supports the vaginal environment 

The innate immune system of the female genital tract includes the vaginal microbiota and different cells and proteins that all work to protect the female from pathogens.13
The human vagina and the indigenous bacterial communities residing in it are an example of a balanced, mutualistic relationship. In this relationship, the host provides benefits to the microbial communities in the form of the nutrients needed to support bacterial growth. In return, the indigenous bacterial communities play a protective role by limiting colonization of the host by potentially pathogenic organisms, including those associated with bacterial vaginosis, yeast infections and urinary tract infections.14

Bacteria from the genus Lactobacillus are dominant in the healthy vaginal microbiome

In the majority of women, species of Lactobacillus are dominant in the vagina14 and are thought to play a major role in protecting the vaginal environment from non-indigenous and potentially harmful microorganisms. This is primarily achieved through four mechanisms:15, 16

  1. Microbial competition for nutrients and adherence to the vaginal epithelium
  2. Reduction of the vaginal pH by the production of organic acids, especially lactic acid
  3. Production of antimicrobial substances, such as bacteriocins and hydrogen peroxide, suppressing the growth of several microorganisms
  4. Modulation of the local immune system 

Lactobacilli also dominate the urinary tract microbiome 

The urinary tract microbiome is mostly composed of bacteria from the genus Lactobacillus, and, to a lesser degree, Gardnerella, Streptococcus, Staphylococcus and Corynebacteria. As in the vaginal microbiome, there are microbes with characteristics that are thought to promote a healthy microbiome. For example, some Lactobacillus species that colonize the vagina excrete lactic acid and hydrogen peroxide, inhibiting the growth of uropathogenic E. coli, the most common bacteria causing urinary tract infections.17

Infections can occur when the bacteria in the urogenital area are out of balance


Dysbiosis challenges the urogenital environment

Urinary tract and vaginal infections are common conditions which can occur when the bacteria in the urogenital environment are out of balance (i.e. dysbiosis). The most common infection is bacterial vaginosis. The infection is characterized by a shift in the microbial composition from being dominated by lactobacilli to including and increasing the presence of other bacteria, such as Gardnerella vaginalis, Atopobium spp., and Prevotella spp.18

Vulvovaginal candidiasis is an infection associated with Candida spp. Usually, Candida live in parts of the body such as the vagina without any detrimental effects, but under certain conditions, Candida spp. can become an opportunistic fungal pathogen, with a tendency to overgrow. Candida albicans is responsible for 80–92% of vulvovaginal candidiasis cases.18

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How do urinary tract infections occur?

Urinary tract infections (UTI) often occur due to the presence or dominance of uropathogenic microbes such as E.coli bacteria.17 A UTI typically starts with periurethral contamination by a uropathogen residing in the gut, followed by colonization of the urethra and subsequent migration of the pathogen to the bladder.10, 19

Results from clinical studies suggest that UREX may support the urogenital microbiome

The Chr. Hansen UREX blend is a combination of the GR-1® and RC-14® probiotic strains. The effect of the two strains on the urogenital tract has been extensively researched in human clinical trials. The GR-1® strain was isolated from the distal urethra of a healthy woman, and the RC-14® strain was isolated from the vagina of a healthy woman. Early research associated local application of the two probiotic strains to the vaginal tract with an improvement in the bacterial environment of that area.20, 21 Numerous trials have subsequently investigated the effect of orally consuming the probiotic blend on urogenital health. In these studies, the strains were associated with a positive impact on the vaginal and urinary tract microenvironments, suggesting that the strains pass though the digestive tract, to the vaginal and urinary tracts where they may exert a benefit.1, 2, 3, 4, 11, 12, 22

The Nugent method23 is an assessment of vaginal bacterial dysbiosis: 

0-3 = normal microbiota
4-6 = intermediate microbiota
7-10 = bacterial vaginosis

UREXTM may support vaginal health

In several studies, daily intake of the UREXTM probiotic blend has been associated with improvement of the vaginal microbiota. In a randomized, double-blinded, placebo-controlled clinical trial, women with bacterial vaginosis were randomized to receive placebo or 2 billion CFU/day of UREXTM. After 6 weeks, significantly more women in the UREXTM group demonstrated a restored, balanced vaginal microbiota than women in the placebo group.11

A study of post-menopausal women with an ‘intermediate vaginal microbiota’ (Nugent classification) randomized the women to receive a placebo or 1 billion CFU/day of the UREXTM probiotic blend. After 4 weeks, the women who received the UREXTM blend had an improved vaginal microbiota that was within the normal, healthy Nugent range, whereas the women in the placebo group did not have significantly improved vaginal microbiota.

In two randomized, placebo-controlled double-blinded clinical trials, combining UREXTM at 2 billion CFU/day with antibiotic treatment was associated with greater improvement in bacterial vaginosis and normalization of Nugent score than for antibiotics combined with placebo.3, 12 Read more about probiotics and antibiotics.

The effect of UREXTM supplementation in combination with an antifungal agent to alleviate vulvovaginal candidiasis has been investigated in a randomized, double-blinded, placebo-controlled trial. In the study, women received either an antifungal agent plus UREXTM or the same antifungal agent plus placebo. After four weeks, it was observed that the women who took UREXTM had significantly less vaginal discharge and lower presence of yeast than the women given placebo.4 This suggests UREXTM may have a beneficial adjunctive effect on candidiasis.

UREXTM may help women who experience recurring UTIs

Women with a history of recurrent UTIs were randomized to supplement with UREXTM or low dose antibiotic prophylaxis for one year. Results showed that the number of UTIs experienced by the women was significantly reduced in both groups and there was no significant difference in the number of infections between the groups receiving either antibiotics or UREXTM.2 The results of the study suggest that UREXTM may be beneficial for women with recurring UTIs.

The UREXTM probiotic blend may have an important role in supporting urogenital health

The UREXTM blend is a specific combination of the GR-1® and RC-14® probiotic strains and has been associated with fewer symptoms of vaginal and urinary tract infections. Specifically, clinical studies suggest that UREXTM may promote vaginal and urinary tract health (when used alone and in combination with antibiotic treatment), and has been associated with improved outcomes of antifungal treatment for yeast infections. The UREXTM blend has also been associated with fewer recurrent urinary tract infections.

Read more about our probiotic strains here.

CFU: Colony Forming Unit


GR-1®, RC-14® and UREXTM are trademarks of Chr. Hansen A/S.


The article is provided for informational purposes regarding probiotics and is not meant to suggest that any substance referenced in the article is intended to diagnose, cure, mitigate, treat, or prevent any disease

UREX - a blend of two probiotic strains

The UREX™ blend is a combination of two probiotic bacterial strains, Lactobacillus rhamnosus, GR-1® and Lactobacillus reuteri, RC-14®. UREX™ has been associated with supporting female urogenital health.

UREX™, GR-1® and RC-14® are trademarks of Chr. Hansen A/S

UREX icon

References Open Close

1. Petricevic L, et al. Randomized, double-blind, placebo-controlled study of oral lactobacilli to improve the vaginal flora of postmenopausal women. Eur J Obstet Gynecol Reprod Biol. 2008;141(1):54-7. (PubMed)
2. Beerepoot MA, et al. [A study of non-antibiotic versus antibiotic prophylaxis for recurrent urinary-tract infections in women (the NAPRUTI study)]. Ned Tijdschr Geneeskd. 2006;150(10):574-5. (PubMed)
3. Anukam K, et al. Augmentation of antimicrobial metronidazole therapy of bacterial vaginosis with oral probiotic Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14: randomized, double-blind, placebo controlled trial. Microbes Infect. 2006;8(6):1450-4. (PubMed)
4. Martinez RC, et al. Improved treatment of vulvovaginal candidiasis with fluconazole plus probiotic Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14. Lett Appl Microbiol. 2009;48(3):269-74. (PubMed)
5. Bradshaw CS, et al. Prevalent and Incident Bacterial Vaginosis Are Associated with Sexual and Contraceptive Behaviours in Young Australian Women. PLoS One. 2013;8(3):e57688. (PubMed)
6. Allsworth JE, Peipert JF. Prevalence of bacterial vaginosis: 2001-2004 National Health and Nutrition Examination Survey data. Obstet Gynecol. 2007;109(1):114-20. (PubMed)
7. Chico RM, et al. Prevalence of malaria and sexually transmitted and reproductive tract infections in pregnancy in sub-Saharan Africa: a systematic review. JAMA. 2012;307(19):2079-86. (PubMed)
8. Foxman B, et al. Prevalence of recurrent vulvovaginal candidiasis in 5 European countries and the United States: results from an internet panel survey. J Low Genit Tract Dis. 2013;17(3):340-5. (PubMed)
9. Corsello S, et al. An epidemiological survey of vulvovaginal candidiasis in Italy. Eur J Obstet Gynecol Reprod Biol. 2003;110(1):66-72. (PubMed)
10. Flores-Mireles AL, et al. Urinary tract infections: epidemiology, mechanisms of infection and treatment options. Nat Rev Microbiol. 2015;13(5):269-84. (PubMed)
11. Vujic G, et al. Efficacy of orally applied probiotic capsules for bacterial vaginosis and other vaginal infections: a double-blind, randomized, placebo-controlled study. Eur J Obstet Gynecol Reprod Biol. 2013;168(1):75-9. (PubMed)
12. Martinez RC, et al. Improved cure of bacterial vaginosis with single dose of tinidazole (2 g), Lactobacillus rhamnosus GR-1, and Lactobacillus reuteri RC-14: a randomized, double-blind, placebo-controlled trial. Can J Microbiol. 2009;55(2):133-8. (PubMed)
13. Valenti P, et al. Role of Lactobacilli and Lactoferrin in the Mucosal Cervicovaginal Defense. Front Immunol. 2018;9:376-. (PubMed)
14. Ma B, et al. Vaginal microbiome: rethinking health and disease. Annu Rev Microbiol. 2012;66:371-89. (PubMed)
15. Aroutcheva A, et al. Defense factors of vaginal lactobacilli. Am J Obstet Gynecol. 2001;185(2):375-9. (PubMed)
16. Rönnqvist PD, et al. Lactobacilli in the female genital tract in relation to other genital microbes and vaginal pH. Acta Obstet Gynecol Scand. 2006;85(6):726-35. (PubMed)
17. Brubaker L, Wolfe A. The urinary microbiota: a paradigm shift for bladder disorders? Curr Opin Obstet Gynecol. 2016;28(5):407-12. (PubMed)
18. Ceccarani C, et al. Diversity of vaginal microbiome and metabolome during genital infections. Sci Rep. 2019;9(1):14095. (PubMed)
19. Mueller ER, et al. Female urinary microbiota. Curr Opin Urol. 2017;27(3):282-6. (PubMed)
20. Gardiner GE, et al. Persistence of Lactobacillus fermentum RC-14 and Lactobacillus rhamnosus GR-1 but not L. rhamnosus GG in the human vagina as demonstrated by randomly amplified polymorphic DNA. Clin Diagn Lab Immunol. 2002;9(1):92-6. (PubMed)
21. Burton JP, et al. Improved understanding of the bacterial vaginal microbiota of women before and after probiotic instillation. Appl Environ Microbiol. 2003;69(1):97-101. (PubMed)
22. Reid G, et al. Nucleic acid-based diagnosis of bacterial vaginosis and improved management using probiotic lactobacilli. J Med Food. 2004;7(2):223-8. (PubMed)
23. Nugent RP, et al. Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. J Clin Microbiol. 1991;29(2):297-301. (PubMed)

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