A healthy vagina is home to a diversity of microbes that work in tandem to keep an acidic environment in check. But this balance of flora can be easily disrupted, or shift throughout the menstrual cycle. This is where probiotics might come in, to help replenish the good bacteria, and curb the bad.
Probiotics and the vaginal microbiome
The billions of bacteria, fungi, viruses, and other microbes present in the vaginal canal are known as the vaginal microbiome. When working as it should, the healthy bacteria dominate, keeping harmful bacteria at bay. Typically, these healthy bacteria are mostly made up of Lactobacillus species. You can read more about how the vaginal ecosystem works in our Vaginal Microbiome 101.
What are they?
Probiotics are live bacteria and yeasts that promote healthy functioning in different parts of the body. Probiotic supplements for vaginal health contain beneficial Lactobacillus strains. Think of them as an outside source of ‘good’ vaginal bacteria. Some research suggests they can help restore a balance of vaginal flora, preventing common infections like thrush and bacterial vaginosis (BV).
But while some studies have produced promising results, the body of evidence on probiotics for vaginal health is too small, and inconclusive, to suggest probiotics are beneficial for vaginal flora, generally. Looking ahead, though, there is a growing number of reproductive health organisations focusing their research power on how probiotics work within the vaginal tract. This signals towards a future where we’ll possibly understand how probiotics can, or can’t, impact vaginal health in more depth.
How do they work?
Probiotic supplements for general health often don’t contain cultures that are particularly useful for vaginal health. It’s thought that vaginal probiotics with Lactobacillus strains that are better at sticking to vaginal cells are more effective. Some studies have shown these strains are more likely to populate the vaginal microbiome, and maintain this population over time.
Vaginally inserted probiotics
Probiotics that are inserted directly into the vagina as a pessary gel, capsule, or pill, are able to populate the vagina with Lactobacillus strains faster and in larger quantities than oral probiotics for vaginal health.
Oral probiotics
Vaginal probiotics taken orally have to pass through the digestive tract, often reaching the rectal tract, as well as the vaginal tract after this. Some studies have suggested that oral probiotics for vaginal health can reduce yeast and other pathogenic microbes within the rectum, too. This could possibly reduce the frequency of vaginal infections that occur because of rectal to vaginal transmission.
Though oral probiotics have been proven to be beneficial in a similar way to vaginally inserted probiotics, not all Lactobacillus strains taken orally will survive as they pass through the digestive tract.
The viability dilemma
Even with probiotic supplements created specifically for vaginal health, some don’t contain live cultures at all, or in such low quantities, they are clinically irrelevant. The transport and storage of probiotic supplements can impact their viability, too. Live cultures either need to be consistently frozen to keep them alive, or freeze dried to keep them shelf stable. Some brands 'guarantee’ that the live cultures in their products make it to the vaginal tract alive, offering efficacy proof via self funded research. But this isn’t a requirement.
This can leave us gambling with products that may be ineffective. GRAS regulation in the US does require probiotic supplements to be safe, though. Common Lactobacillus species are generally considered safe under this regulation, though it’s less clear about the full scope of Lactobacillus strains.
Should I be taking probiotics?
Probiotics aren’t normally recommended for vaginal health if you don’t suffer from frequent vaginal infections, or other genital health issues. In the absence of these issues, it’s likely that your vaginal flora is already balanced and healthy. Supplementing a healthy vaginal microbiome with a probiotic is unlikely to produce any additional benefits.
Probiotics might be especially beneficial after a course of antibiotics, where your body’s natural supply of healthy vaginal flora has been depleted. Supplementation can help kick start the growth of these healthy microbes again.
Probiotic supplements are considered safe for the average person. But there is a small risk to those with compromised immune systems, in theory.
Plus, despite some clinical backing, the Lactobacillus strain relevant for each type of flora imbalance differs. This complicates selecting the right product, and not all strains will work for everyone.
If you are keen on trying vaginal probiotics for preventing thrush, BV, vaginal dryness, or UTIs, you’re more likely to see results faster with vaginally inserted probiotics, compared to oral probiotics, if at all. Look for products with high viable cell counts of one or more of the following: L. crispatus, L. gasseri or L. jensenii.
Looking ahead
As it stands, there is not enough conclusive evidence that paints probiotics as a viable answer to common vaginal health issues, yet. While some clinical research has found positive correlations between probiotic supplementation and a reduction in thrush, BV, UTIs, vaginal dryness, or other genital tract issues — larger scale studies, efficacy and safety data are needed to propel the vaginal probiotics space ahead.
References
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Attributions
Rachel Mantock is a London-based health, lifestyle and culture journalist and content consultant, with a focus on the healthcare access barriers faced by marginalised groups. She hates cooking, but secretly enjoys doing laundry, and is most likely binge watching an American Horror Story series right now. You can find her @rachelmantock on Twitter and Instagram, rattling off about cuts to SRH services, and cookie crisp (it’s a mixed bag).
Read MoreRuth Richards was a Scientist at Juno Bio where she worked on the development of our metagenomics discovery platform. She holds a MSc in Bioinformatics and Theoretical Systems Biology from Imperial College London.
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