Probiotics for women: what the research shows

Is there a probiotic made for women?

Expert bodies of health professionals make no recommendations for or against the use of probiotics by healthy people.¹

Different probiotics can have different effects. If one kind of Lactobacillus helps, that does not mean another kind of Lactobacillus, or any Bifidobacterium, will do the same.⁸

A product sold to women is judged like any other probiotic: by the strain names on the label, the count through the expiration date, and whether those exact strains were tested for what you want. Pink packaging or the word women on the front tells you nothing about the organisms inside.^1,9

Vaginal bacteria: what the trials measured

Lactobacilli are the bacteria researchers look for in vaginal samples, so trials in this area count them before and after a probiotic. Most of this work tested a single pair of strains.^2,6

A 2019 review of 45 studies in healthy adults included four on women's reproductive health and found evidence that probiotics can raise the amount of lactobacilli in vaginal samples.⁶

In a 2003 trial in 64 healthy women, two strains taken by mouth for 60 days, Lactobacillus rhamnosus GR-1 and Lactobacillus fermentum RC-14, raised lactobacilli and lowered yeasts and coliform bacteria in vaginal samples compared with placebo, with no adverse effects.²

Two later trials gave the same two strains to pregnant women, with 238 and 66 women analyzed. Neither found a change in vaginal bacteria compared with placebo.^3,4

Put together, one positive trial in women who were not pregnant and two trials with no effect in pregnant women make this early evidence for two named strains. It does not transfer to products made with other strains, including ours, and none of these trials measured comfort or how women felt.^2,3,4

After menopause

We found no probiotic trial in healthy women over 50 with a result we could grade. NCCIH lists research on how probiotics might act on bone after menopause among the projects it funds, which makes it work in progress rather than a finding.⁸

For digestion, the advice is the same at any age: no official recommendation for healthy people, results tied to named strains, and a label count that should hold through the expiration date.^1,9

What's in ours

None of our products contains the GR-1 and RC-14 strains from the vaginal studies, and none has been tested in women specifically.²

Pregnancy and breastfeeding

In trials in pregnancy, Lactobacillus and Bifidobacterium probiotics did not change rates of cesarean birth, birth weight or length of pregnancy, and a 2021 review found no serious problems for mother or infant. One study reported more vaginal discharge and changes in stool with L. rhamnosus and L. reuteri. No trials have tested Saccharomyces yeast in pregnancy, so its safety there is unknown.^5,7

Those reviews are reassuring for the two most studied groups of bacteria, but they pooled many different products and were not designed to find rare problems. Ask your doctor or midwife before starting a probiotic while pregnant or breastfeeding, and avoid yeast-based products unless they advise one.^5,7

Symptoms need a diagnosis, not a supplement

NCCIH advises against using probiotics as a reason to put off seeing a health care provider about any health problem. That includes new vaginal itching, discharge or odor, and burning when you urinate, which can come from infections that need testing and the right treatment.⁸

A 2015 review cited by NCCIH found no evidence that probiotics prevent urinary tract infections.⁸

• Ask your doctor first if you have a weakened immune system, for example during chemotherapy or after a transplant⁹
• Ask first if you are seriously ill or in hospital¹
• Ask first if you take an antibiotic or an antifungal medicine, since NIH says these might make some probiotics less effective¹⁰

Questions people ask

Sources

1. Office of Dietary Supplements, National Institutes of Health. Probiotics: Fact Sheet for Health Professionals. Updated March 25, 2025. Opened 2026-10-07.
2. Reid G, Charbonneau D, Erb J, 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;35(2):131-134. Opened 2026-10-07.
3. Husain S, Allotey J, Drymoussi Z, et al. Effects of oral probiotic supplements on vaginal microbiota during pregnancy: a randomised, double-blind, placebo-controlled trial with microbiome analysis. BJOG. 2020;127(2):275-284. Opened 2026-10-07.
4. Yang S, Reid G, Challis JRG, et al. Effect of oral probiotic Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 on the vaginal microbiota, cytokines and chemokines in pregnant women. Nutrients. 2020;12(2):368. Opened 2026-10-07.
5. Sheyholislami H, Connor KL. Are probiotics and prebiotics safe for use during pregnancy and lactation? A systematic review and meta-analysis. Nutrients. 2021;13(7):2382. Opened 2026-10-07.
6. Khalesi S, Bellissimo N, Vandelanotte C, et al. A review of probiotic supplementation in healthy adults: helpful or hype? Eur J Clin Nutr. 2019;73(1):24-37. Opened 2026-10-01.
7. Dugoua JJ, Machado M, Zhu X, et al. Probiotic safety in pregnancy: a systematic review and meta-analysis of randomized controlled trials of Lactobacillus, Bifidobacterium, and Saccharomyces spp. J Obstet Gynaecol Can. 2009;31(6):542-552. Opened 2026-10-07.
8. National Center for Complementary and Integrative Health. Probiotics: Usefulness and Safety. Last updated August 2019. Opened 2026-10-07.
9. Office of Dietary Supplements, National Institutes of Health. Probiotics: Fact Sheet for Consumers. Updated November 17, 2025. Opened 2026-10-07.
10. Office of Dietary Supplements, National Institutes of Health. Dietary Supplements for Immune Function and Infectious Diseases: Fact Sheet for Consumers. Updated March 10, 2025. Opened 2026-10-07.