There’s no real reason to put live microorganisms in your vagina — but that doesn’t stop companies from selling them or saying they work.
Vaginal Probiotics
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Drugstore shelves and the internet are full of curious new products claiming to support vaginal health. Whether it's the "vajayjay spray" with probiotics and prickly pear extract recently endorsed by Oprah, or an obscure "odor-eliminating film" to freshen already-healthy and self-cleaning nether regions, it seems everyone is trying to sell something to make vulvas either "smell and taste like nothing" — or cure uncomfortable symptoms that should be seen by a doctor. 

Some practices, like vaginal douching and steaming, are already widely known for doing more harm than good. But other purported wellness products are more confusing. Vaginal probiotics sound like they're based on science; they're touted as a way to introduce live microorganisms into your vagina to improve health. We know that there is some evidence that shows certain probiotics can be good for our gut… but can vaginas really benefit from them, too, or are they just another way for companies to profit from vaginal shame?

"I see patients with complex vaginitis cases [inflammation of the vagina that causes discharge, itching, and pain] every single day and almost every one of them is taking probiotics or had previously taken them and abandoned them due to lack of efficacy," says Jen Gunter, M.D., an ob-gyn famous on social media for calling out products you should not put in your vagina. "Obviously if these products worked I wouldn't be seeing these patients." 

Dr. Gunter, author of the bestselling Vagina Bible, adds that when she started practicing 30 years ago, no one seeing her for vaginitis — such as yeast infections or bacterial vaginosis — was taking probiotics. "Now it seems almost everyone is, but I don't see any drop in the rates of vaginitis."

Vaginal probiotic products include oral pills and powders and suppository capsules that are inserted vaginally. It's easy to see the appeal of these products, especially when you're suffering from chronic discomfort from conditions such as bacterial vaginosis, yeast infections, or urinary tract infections (UTIs). But the problem is, you don't really know what you're getting or how it will affect your body.

The vagina, like the gut, has been well studied. Research shows that it is teeming with a diversity of microbes, including bacteria, that are important for health. Some common gynecological conditions are thought to be caused by an imbalance of bacteria inside the vagina. But experts say that the right balance of bacteria is still unknown, and despite an increase in data, researchers have yet to replicate the benefits of bacteria in therapeutic form.

Jacques Ravel, Ph.D., a vaginal microbiome researcher and professor at the University of Maryland, points to three of the most common vaginal bacteria species: lactobacillus crispatus, lactobacillus gasseri, and lactobacillus jensenii. But he says until there are more FDA-supervised clinical trials — large, randomized, double-blind studies — that prove they work, it's too easy for companies to fudge their effectiveness. 

Ravel is a primary investigator in the vaginal health division of the National Institutes of Health's Human Microbiome Project and founder of  LUCA Biologics, which is currently running a clinical trial to test live bacteria to treat UTIs. "One of the challenges we have is that there's no animal model," Ravel says. In women, lactobacillus in the vagina is critical. That's not the case in the animal kingdom. "There's no lactobacillus in the vagina of any animal where it plays a central role, which makes studies more complicated."

For example, one clinical trial published in The New England Journal of Medicine studied women who were initially treated for bacterial vaginosis who inserted a type of probiotic called Lactobacillus crispatus (Lactin-V) in their vagina twice per week. The performance? Not great, notes Dr. Gunter. Researchers found a 30% recurrence rate of bacterial vaginosis at 12 weeks versus 45% for placebo. "It's a start for sure, but that's it."

Most of the existing studies on vaginal probiotics are poorly done and don't adhere to rigorous research standards, including large sample sizes, long-term clinical trials, randomized control groups, and being published in peer-reviewed journals. So don't be tricked by a brand making claims that sound legitimate but aren't backed by sound scientific conclusions.

Dr. Gunter agrees the evidence is negligible, adding there isn't any good data to support any over-the-counter probiotic for vaginal or urinary tract health. "Consumers have no way of knowing if these products even contain what they claim. The vaginal microbiome is very complex and it changes constantly and we in medicine don't fully understand these changes," she says. (Some of those fluctuations have been linked to hormone cycles, diet and even exercise.)

"In addition, we [all] have different microbiomes, so what might be right for me might not be right for you. So the idea that a company promoting an untested product has the answers is ludicrous," Dr. Gunter adds. 

Yet that doesn't stop companies from selling these products or saying they work. The commercial market for probiotics is expected to reach over $64 billion in sales by 2023. Since all products currently available in the U.S. are classified under supplements, unlike medications, they aren't FDA-regulated, which ultimately makes claims on packaging even more misleading and confusing for consumers. 

"The whole regulatory framework is like a drive to the bottom," says Pieter Cohen, M.D., an associate professor at Harvard Medical School and an internist at Cambridge Health Alliance. To begin with, he says, the name probiotics is a misnomer for many of these products, because the World Health Organization defines probiotics as microorganisms that are beneficial for health, while these are simply live bacteria that for the most part have not been proven to be beneficial, or even safe.

"The reason that happens is not that these companies are involved with anything illegal," says Dr. Cohen. "It's written into the law that companies can promote something as if it has beneficial effects in humans, even if there's no evidence from a single clinical trial that it actually works." FYI, that law was passed in 1994.

Jonathan Eisen, Ph.D., is a microbiologist at UCDavis who hands out an "overselling the microbiome award." While he studies the benefits of probiotics, he's also skeptical of the overhyped industry it's become. "They're sort of allowed to live in this Never Never Land of supplements and they make claims that are scientifically unsound if not absurd."

What's more worrying is that companies appear to be cashing in on vaginal shame by selling products for general wellness and fueling patriarchal, misogynistic expectations that normal female genital anatomy is something that needs to be fixed.

According to Eisen, much of the research on the vaginal microbiome has potential. The problem is it's being marketed to people who don't need it. "They're taking people who are in a position of weakness about something whether it's emotional or medical or whatever." 

That is, probiotic companies are taking advantage of both ubiquitous insecurities and complex vaginal conditions for which people are desperate to find solutions, driving women to try anything from putting garlic cloves straight into their private parts to soaking tampons in yogurt. (There is no evidence that either of these practices brings any relief.)

"Brands capitalize on people's discomfort with vaginas. They make people feel like vaginas are dirty and shameful," says Caroline Mitchell, M.D., an associate professor of obstetrics, gynecology, and reproductive biology at Harvard Medical School. "People don't want to talk about vaginal symptoms, even with health care providers, and feel more comfortable going to a drugstore and just getting something [over the counter] — but there isn't good data to show that any of those things are helpful."

For the most part, the only proven treatments for bacterial vaginosis, yeast infections, and urinary tract infections are antibiotic or antifungal treatments. Experts agree that if you have a vaginal health concern and your own provider hasn't been able to help, seek out a specialist in vulvar and vaginal health conditions. Don't buy an untested over-the-counter product.  

And if you don't have a vaginal health concern? Then, just stay away from vaginal probiotics altogether, says Dr. Gunter. Why test a probiotic, she adds, and risk it not working when people are already buying it on faith? "We definitely need more research here and hopefully we will see more quality studies. However, I am not holding my breath."