Probiotics for Vaginal Health​

The vagina is home to a complex community of microorganisms that are a major part of vaginal health. Probiotics, particularly those containing beneficial Lactobacillus strains, may help support a healthy vaginal microbiome. But does it matter whether you take a probiotic by mouth or use it vaginally?​

Like the digestive tract, the vagina is home to various natural bacteria that can influence vaginal health. This diverse community of microorganisms is collectively known as the vaginal microbiome.

In a healthy reproductive-age woman, Lactobacillus bacteria are often among the dominant members of the vaginal microbiome and produce lactic acid to help maintain an acidic vaginal environment. A lower vaginal pH (acidic) makes it more difficult for some potentially harmful bacteria and other microorganisms to grow and take over.

The vaginal microbiome can be disrupted by several factors, including antibiotics, hormonal changes, sexual activity, and other changes in the vaginal environment. When beneficial bacteria decrease and other microorganisms become more abundant, the resulting imbalance can contribute to problems such as bacterial vaginosis and vulvovaginal candidiasis.

Probiotics have been on the market for gut health for decades, but we’re seeing them marketed for vaginal health more and more these days. Research into probiotics is encouraging, particularly for reducing recurrence and supporting a healthy vaginal microbiome, but the benefits can vary depending on the specific probiotic strain, dose, formulation, and route of administration – oral versus vaginal.

Effects of Probiotics

​Lactobacillus bacteria produce lactic acid and other antimicrobial substances, compete with potentially harmful microorganisms for space on vaginal cells, and contribute to the vaginal environment that helps keep undesirable bacteria and yeast in check. Some strains may also interact with the body’s immune system and support the protective barrier of vaginal tissues.

Bacterial vaginosis (BV) is one of the most common vaginal infections and occurs when the normal balance of bacteria in the vagina changes: bacteria such as Gardnerella vaginalis and Prevotella become more abundant while beneficial Lactobacillus bacteria decrease. Research suggests that certain probiotic strains may be helpful when used alongside standard BV treatment. An analysis of 17 studies involving over 3,000 women found that probiotics were more effective than placebo and that combining probiotics with antibiotics was more effective than antibiotics alone.¹

Vulvovaginal candidiasis, aka yeast infection, also coincides with an unbalanced microbial environment. When Candida, a type of fungus that can normally be present in the vagina without causing problems, grows excessively, it can cause intense itching, irritation, redness, abnormal discharge, painful urination, or discomfort during sex. Certain Lactobacillus strains, including L. crispatus and L. gasseri, have been studied for their ability to inhibit the growth of Candida.²

Researchers have also looked into the role of probiotics in supporting the relief of menopausal symptoms.³ Genitourinary syndrome of menopause (GSM) describes vaginal, vulvar, and urinary changes related to declining estrogen levels during perimenopause and menopause that lead to vaginal dryness, itching, burning, painful sex, urinary urgency and frequency, and recurrent urinary tract infections (UTIs). Estrogen normally helps maintain the thickness, elasticity, moisture, and acidity of vaginal tissues, and as levels decline, the vaginal environment can change, including a reduction in beneficial Lactobacillus bacteria. Some research suggests that probiotics may help support the vaginal microbiome during this transition. Studies of L. rhamnosus GR-1 and L. reuteri RC-14, for example, demonstrated improvements in specific measures of vaginal health and GSM symptoms in postmenopausal women. Research has also suggested that combining probiotics with vaginal estrogen may complement one another.³

A probiotic is defined by its specific strain, not simply by its species, so not every probiotic works the same way. For example, L. rhamnosus GR-1 and L. rhamnosus GG are different strains with different effects – vaginal health benefits cannot automatically be applied to every supplement containing Lactobacillus. That said, the evidence is promising regarding the strains that have been studied as a potential addition to standard treatment when an infection is present.

Oral vs. Vaginal Probiotics

​Probiotics can support vaginal health, but does it matter how you take them? Possibly. Oral and vaginal probiotics work through different routes, and each has potential advantages.

Oral probiotics have to travel through the digestive tract before they can potentially influence the vaginal microbiome. While studies have found benefits from some oral probiotic strains, researchers have not consistently demonstrated that bacteria taken by mouth permanently colonize the vagina. In particular, there is limited evidence that orally consumed L. crispatus can establish itself in the vaginal microbiome. But…

Oral probiotics may still have an indirect effect. The gut and vaginal microbiomes are connected through microbial, immune, and hormonal pathways, and changes in one environment may influence the other. Oral probiotics are also relatively easy to incorporate into a daily routine, which may make them a practical option for long-term use.

Administered as a vaginal suppository, probiotic microorganisms are delivered directly into the vagina. Once there, beneficial Lactobacillus strains may attach to the vaginal lining and compete with potentially harmful microorganisms for available attachment sites, crowding out the “bad guys.” Vaginal probiotics might act more quickly at the intended site than oral probiotics, although the amount of time the bacteria remain in the vagina and whether they establish long-term colonization can vary. But even when probiotics don’t lead to “permanent” colonization, they may still provide transient benefits (like modulation of local immune responses or pH) while they are passing through or present.

Research hasn’t established one route as universally better than the other — direct administration may provide more targeted activity, while oral probiotics have practical advantages and could provide broader effects through the gut.

The specific probiotic strain may also matter more than whether a product is taken orally or vaginally. The gut and the vagina are each home to different combinations of microbial strains, and probiotics are living microorganisms, so the product needs to contain the intended strain in an adequate amount. The best choice will depend on your goals and preferences.

Research into probiotics for vaginal health is still evolving, and no single approach works for everyone. If you decide to try a probiotic, pay attention to how you feel and whether you are actually getting the benefit you hoped for. If it is helping, great. If you are still experiencing symptoms or simply aren’t getting the results you’re looking for, we’ll explore other options or combinations of options together.

At Aayla, we understand that vaginal health is personal, and finding the right approach may take some individualization. Our goal is to help you understand your options and find an approach that fits your needs.​

(Note: Probiotics may reduce the likelihood of recurrent infections when used along with appropriate medications, but they do not take the place of medical guidance.)

References:

1. Wu, L.-Y., Yang, T.-H., Ou, Y.-C., & Lin, H. (2024). The role of probiotics in women’s health: An update narrative review. Taiwanese Journal of Obstetrics & Gynecology, 63(1), 29–36. https://doi.org/10.1016/j.tjog.2023.09.018.
2. Patki, A., Pandit, S., Ashraf, N., Makhwana, S., & Ghosh Dastidar, B. (2025). Expert Opinion on the Use of Probiotics in General Gynecological Conditions. Cureus, 17(3), e80875. https://doi.org/10.7759/cureus.80875.
3. Wu, L.-Y., Yang, T.-H., Ou, Y.-C., & Lin, H. (2024). The role of probiotics in women’s health: An update narrative review. Taiwanese Journal of Obstetrics & Gynecology, 63(1), 29–36. https://doi.org/10.1016/j.tjog.2023.09.018.