By Rachel E. Gross
Before there were vaginal probiotics, there was the yogurt douche. In the 1970s, a common home remedy for yeast infections and other irritating ailments was to soak a tampon in plain, unsweetened yogurt and insert it into the vagina. The same live bacteria that make yogurt beneficial for the gut, the thinking went, might also be good for the vagina.
Though yogurt douching never went commercially mainstream, the concept of infusing an ailing vagina with good bacteria has, in the form of vaginal probiotics.
Many of these products’ claims are vague, but some are bolder in their advertising, promising to prevent or treat common vaginal problems like yeast infections and bacterial vaginosis. But do they actually work? Here’s what we know.
How does the vaginal ecosystem get out of whack?
Think of the vaginal microbiome as a rainforest: a unique ecosystem teeming with microscopic life including bacteria, viruses, and yeast. For many premenopausal women, the dominant microbes are certain species of a bacterial group called Lactobacillus. Other members of this group live in the gut and fermented dairy products like yogurt and cheese.
But the Lactobacillus in the vagina is special. They’ve likely adapted over thousands of years to digest sugars shed by vaginal cells and spew out lactic acid, creating a mildly acidic environment that is inhospitable to bacterial invaders. This helps form a crucial barrier between you and not-you, protecting your reproductive tract from infection and disease.
Lots of things can disrupt vaginal Lactobacilli, including antibiotics, menstruation, douching, certain sexually transmitted infections, and semen. When Lactobacilli numbers fall, other bacteria or yeast normally present in the vagina can overgrow, causing various types of imbalance.
So are vaginal probiotics the solution to yeast infections and B.V.?
Based on what experts know, vaginal probiotics must satisfy two criteria to be effective: They should contain a vaginal strain, like Lactobacillus crispatus, that has been shown to protect against infection; and they should be inserted directly into the vagina.
Most of the products on the market, however, don’t check both of those boxes. Many oral and suppository probiotics contain bacterial species cultivated from the gut or from fermented foods that aren’t natural inhabitants of the vagina.
And the majority of vaginal probiotics on the market are oral capsules, which studies suggest are unlikely to alter vaginal flora. That’s because the bacteria would have to make the treacherous journey down through the gut, out the anus, and then crawl their way over to the vagina.
In a 2020 review of studies on 22 vaginal probiotics taken as suppositories, all were found to be safe.
In the future, there may be research-backed ways to strengthen the vagina’s bacterial defenses, possibly by combining effective probiotics with antibiotics or even by performing vaginal microbiome transplants.
But for now, experts simply don’t know enough about the vaginal microbiome to be able to reliably shift it in the direction of better health. So, while vaginal probiotics are unlikely to hurt you, they also aren’t likely to help you — whether you have an infection or not.
(Courtesy: New York Times)