Physician's Choice
Probiotics for Vaginal Health: Which Strains Were Studied and How to Choose
Updated Oct 26, 2026 · 11 sources
Probiotics for vaginal health are probiotic supplements built on Lactobacillus, the bacteria that lead a healthy vaginal flora.1 Taken by mouth, GR-1 with RC-14 went with a healthy flora score in up to 90% of women in one trial, and in women past menopause with mid-range swab scores it improved those scores by two or more points in 60%, against 16% on placebo.2,3 Choose by strain code.
Key points
- In a 28-day trial in 42 healthy women, GR-1 with RC-14 by mouth went with a healthy flora score in up to 90%, while a different strain, GG, had no effect.2
- In 72 women past menopause whose swabs scored mid-range, 14 days of the pair by mouth improved those scores by two or more points in 60%, against 16% on placebo.3
- Physician’s Choice Vaginal Probiotic lists all three of its strains with codes, Lacticaseibacillus rhamnosus GR-1™, Limosilactobacillus reuteri RC-14™ and Lactobacillus crispatus LBV88™, at 6 billion CFU per capsule (See the label); the trials above did not test this product.4
What are probiotics for vaginal health?
Probiotics picked for the vagina rather than the gut. A 2026 review describes certain probiotics as live microorganisms that, given in adequate amounts by mouth or vaginally, help maintain a balanced microbial environment.5 Cleveland Clinic explains that lactobacilli make lactic acid and hydrogen peroxide, which help keep vaginal pH slightly acidic, a setting that makes it hard for unhealthy bacteria to grow.1
Do probiotics help vaginal health?
For some strains, trials found healthier vaginal flora in some women; results depend on the strain and on who takes it. In a 2001 trial, 42 healthy women took GR-1 with RC-14, or a different L. rhamnosus strain called GG, by mouth for 28 days; at entry, only 40% had normal flora. Taken once or twice a day, the pair went with a healthy flora score in up to 90% of women, and GG “failed to have an effect.”2
In a 2008 trial, 72 women past menopause whose first swab scored 4 to 6 on the Nugent scale took the pair by mouth for 14 days; a day later, scores had fallen two or more points for 60% on the probiotic versus 16% on placebo.3 GR-1™ and RC-14™ were studied together in a 2003 randomized, placebo-controlled trial in which 64 healthy women took them by mouth for 60 days and researchers measured vaginal flora (Reid and colleagues; RC-14™ was then named L. fermentum RC-14™).6
Taken for 8 weeks in early pregnancy (320 women), the pair left the normal-flora share no different from placebo.7 Many other trials enrolled women with a vaginal or urinary condition, which a doctor diagnoses; this page leaves those results to the papers.
Which probiotic strains were studied for vaginal health?
Lactobacillus strains. A 2026 review lists six Lactobacillus species for vaginal health, L. crispatus, L. rhamnosus, L. gasseri, L. jensenii, L. reuteri and L. fermentum, calls GR-1 “a well-studied probiotic strain” and says RC-14 is frequently found alongside it. It adds that strains, delivery method and dosage still need standardization.5
The 2001, 2008 and pregnancy trials scored swabs on the Nugent scale, a lab score of bacteria seen under a microscope.2,3,7 Our Vaginal Probiotic strains page takes the three strains on our label one by one.
Oral or vaginal probiotic: which route was studied?
Both, and the swallowed capsule more often. A 2021 review of vaginal probiotic research says oral and vaginal use are “in continuous discussion,” but that “the oral route is used and studied more often despite the need for further transference to the colonization site.”8
What is the best probiotic for vaginal health?
The one whose label you can hold up against the research. Look for a code after every strain, a CFU count with the date it holds to, a route the trials used, a storage line and every other ingredient with its amount. ODS says the label is where you find the genus, species and strain of each microorganism, the expiration or use-by date and storage instructions.9
| What to check | Why it matters | Physician’s Choice Vaginal Probiotic, as printed |
|---|---|---|
| A code after each strain | ODS says probiotics are named down to the strain, and a product’s benefits, if any, are set by its strains and CFU count9 | Lacticaseibacillus rhamnosus GR-1™, Limosilactobacillus reuteri RC-14™ and Lactobacillus crispatus LBV88™4 |
| The CFU count, and when it is counted | Counts can fall over time; ODS notes that some experts prefer a count that holds to the expiration or use-by date9 | Total Probiotic Activity: 6 Billion CFUs for the 70 mg blend4 |
| How you take it | The GR-1 and RC-14 trials here gave daily doses by mouth2,3,7 | 1 capsule by mouth, 30 servings; the product page says one capsule daily with water4 |
| Storage | Some probiotics need the refrigerator and some keep at room temperature, ODS says9 | The product page image reads: no refrigeration required4 |
| Everything else in the capsule | These are not probiotics; check each against any allergy | Organic acacia fiber 150 mg, organic cranberry (fruit) extract 75 mg, deglycyrrhizinated licorice root extract 50 mg, in a vegetable capsule (hypromellose, gellan gum) with rice flour, rice hull concentrate, gum arabic and sunflower oil4 |
For the same checks on any probiotic, see our guide to choosing a probiotic. Cranberry and D-mannose are covered on our page on what a women’s probiotic does.
Where Physician’s Choice fits
- Vaginal Probiotic. Its label reads: 6 Billion CFUs to promote vaginal health‡. Vaginal Probiotic is formulated to help balance vaginal pH‡. Three coded strains in a 70 mg blend, 1 capsule a day by mouth.4 The trials above tested GR-1™ and RC-14™ in their own capsules, not this product. See the label.
Safety: when to see a doctor first
See your doctor or ob-gyn if you notice itching, burning, a bad odor or a lot of discharge. ACOG says these can come from a vaginal condition, which a doctor diagnoses: an ob-gyn takes a sample of the discharge to find the cause.10 NCCIH says not to use probiotics as a reason to put off seeing your health care provider about any health problem.11
If you are pregnant or breastfeeding, are seriously ill, or have a weakened immune system, consult your healthcare provider before taking a probiotic or any other dietary supplement.
If you have known allergies, review the product’s ingredient list and allergen information and consult your healthcare provider before purchasing or using it. Most of our products are formulated without the top 9 common allergens, but ingredients vary by product.
Side effects
According to the NIH Office of Dietary Supplements, probiotics are generally well tolerated by healthy people, though they may cause mild digestive symptoms, such as gas. Probiotics may not be appropriate for everyone, particularly people who are seriously ill or have weakened immune systems. Talk with your healthcare provider before use.
If you experience an adverse event, stop using the product and contact your healthcare provider immediately. Please also notify us at support@physicianschoice.com or 1-877-395-2707.
Questions women ask
What are probiotics for vaginal health?
Probiotic supplements built on Lactobacillus strains, the bacteria that lead a healthy vaginal flora. Choose one by strain code, and take any new symptom to a doctor.
How long do vaginal probiotics take to work?
The trials on this page gave GR-1 with RC-14 by mouth and checked vaginal flora after 14 days, 28 days, 60 days and 8 weeks of daily use, with differing results. None of them sets a date that applies to every woman.
Women’s probiotic vs vaginal probiotic: which one is for vaginal flora?
Our Vaginal Probiotic lists 3 coded strains, including GR-1™ and RC-14™, the pair tested in the trials on this page; our Women’s Probiotic is an everyday formula. Our page What is the best probiotic for women? compares the two labels.
Is a vaginal probiotic swallowed or inserted?
Either, by product; a 2021 review says the oral route is studied more often. Physician’s Choice Vaginal Probiotic is a capsule you swallow, one a day.
The short version
Probiotics for vaginal health are Lactobacillus supplements. Choose by strain code and a complete label, and take any new symptom to a doctor.
Sources
- Cleveland Clinic. Vaginal Flora. Last updated February 13, 2026.
- Reid G, et al. Probiotic Lactobacillus dose required to restore and maintain a normal vaginal flora. FEMS Immunol Med Microbiol, 2001.
- 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.
- Physician’s Choice. Vaginal Probiotic product page and Supplement Facts label (30 count).
- Sahu BK, et al. The role of probiotics in restoring and maintaining vaginal microbiome health: a review. Infect Immun, 2026.
- Reid G, et al. 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.
- Gille C, et al. Effect of probiotics on vaginal health in pregnancy. EFFPRO, a randomized controlled trial. Am J Obstet Gynecol, 2016.
- López-Moreno A, Aguilera M. Vaginal Probiotics for Reproductive Health and Related Dysbiosis: Systematic Review and Meta-Analysis. J Clin Med, 2021.
- NIH Office of Dietary Supplements (ODS). Probiotics: Fact Sheet for Consumers. Updated November 17, 2025.
- American College of Obstetricians and Gynecologists (ACOG). Patient FAQ028. Last updated December 2025.
- National Center for Complementary and Integrative Health (NCCIH). Probiotics: Usefulness and Safety. Last updated August 2019.
How this page was made
Sources fetched October 26, 2026. Label facts come from our Vaginal Probiotic label and product page, read the same day. Written by Physician’s Choice.
‡These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.