The vaginal microbiome: how to look after it – and what to avoid

‘Us girls, we have a lot of problems down there and it’s an absolute nightmare,” one influencer says on TikTok, like a seasoned teleshopping host. She reels off a list that includes thrush, bacterial vaginosis (BV) and urinary tract infections – common issues that many women are too shy, insecure or squeamish to talk about. But she has an answer to these woes: vaginal probiotic pills. These are being touted on the social media site as magical new supplements that can improve the health of your vaginal microbiome.

But what is the vaginal microbiome? And does it need to be fixed? According to Ina Schuppe Koistinen, an associate professor at the Karolinska Institutet in Sweden and an expert in the subject, the term refers to the gene content of the microbes in that area of the body. “You can also call it the vaginal microbiota – or vaginal flora – and it means all the microbes that are present. That’s bacteria, but also viruses, fungi and all kinds of single-cell organisms.” We all have microbiota in other parts of the body, too, including on the skin and in the gut. The health of the microbiome is determined by the delicate balance of microbes.

Only about 1% of healthcare research and innovation is invested in female conditions beyond oncology

A healthy vaginal microbiome would be dominated by lactobacilli, especially the species called lactobacillus crispatus. These bacteria are our first protection against infections. They help keep the pH of the organ low (yes, vaginas have their own pH, usually somewhere between 3.8 and 4.5) and create an environment that is hostile to other pathogenic bacteria that might knock the microbiome out of balance and cause infections such as BV and thrush.

Infections arise when this careful balance of bacteria is upset. The main culprits? Fragranced soaps, harsh detergents and antibiotics, which can kill off the “good” as well as the “bad” lactobacilli. Unprotected sex also exposes you to bacteria in other people’s microbiomes; the more partners, the more potential varieties. Smoking can have an effect, too, because it can reduce the prevalence of the bacterium that protects the area from infection, meaning your chances of developing thrush or BV increase.

“Most women have small amounts of fungi in their vaginas, but when they take over it can cause a fungal infection like thrush,” Schuppe Koistinen says. “Semen has a neutral pH and adds nutrients to the vagina that make bacteria other than lactobacilli grow and take over.” Menstrual blood can also affect and raise the pH level, making the environment less favourable for lactobacilli and leading to an unbalanced microbiota.


Back to the probiotics being touted on social media. You can see why products claiming to “support the vaginal flora” or “restore the natural environment in the vagina” might be popular. But do they deliver?

“Most probiotics you can buy are not tested in clinical trials for what they are supposed to do,” says Schuppe Koistinen. “They are commonly used bacterial strains that are easy to produce and sell.” Probiotics, found in some foods and often taken as supplements, are live bacteria that are thought to increase the variety of microscopic organisms in different parts of the body. They are marketed to help with a range of health problems, from bloating to vaginal odour, but the science behind them is ambiguous.

There are, Schuppe Koistinen says, no probiotics available that contain the species of lactobacillus that scientists have identified as supporting good vaginal health. These kinds of products contain lactobacillus plantarum, lactobacillus rhamnosus and bifidobacterium animalis lactis – not commonly found in the vagina and probably derived from the gut or found in fermented foods, she says. Even if these did end up in the right place, they probably wouldn’t thrive there and would most likely die. “The commercial companies selling these probiotics are very smart … but until there are studies that show real, significant effects, a very big part of it is probably a placebo effect,” she says.

A woman holding a menstrual cup
Using a menstrual cup can help your vaginal microbiome. Photograph: Volanthevist/Getty Images

“If something sounds too good to be true, it usually is,” says Dr Jen Gunter, a gynaecologist and the author of The Vagina Bible. “If there were a magical supplement to solve myriad vaginal problems, we would prescribe it. If something is making any kind of quasi-health claim and it’s not approved by a regulatory board, then those claims are highly suspect.”

Keeping vaginas happy might sound like a minefield, but often what works is leaving them to do what they do best: clean and protect themselves naturally. “The vagina is a self-cleaning organ. It has its own way of keeping the balance,” says Michelle Swer, a consultant gynaecologist. This means you should avoid douching – trying to clean inside the vagina – because it can harm this balance, or exacerbate an existing problem. The vulva, on the outside, can be cleaned “with water and a mild soap only”.

Vaginas have an inbuilt “plasticity”: if the microbiome is disrupted, it can usually correct itself. “We are all made for having menses and sex, so if you have a healthy microbiome, it tends to go back to its normal conditions,” says Schuppe Koistinen. “If you live a healthy life and eat well, sleep well and have safe sex, then you normally don’t even have to think about it.”

There are, however, small changes you can make. Using a menstrual cup instead of a tampon or a pad can help, because it “catches” blood from higher up in the vagina, so blood doesn’t sit for long periods of time. Using condoms for the first few months of sex with a new partner can also limit the effects that contact with other bacteria can have on the microbiome. Introducing more fermented foods, such as sauerkraut, kimchi, kefir and kombucha, can be beneficial.

Schuppe Koistinen notes that poor education about women’s health also plays a part. “As young girls, we don’t learn how a healthy vagina should look and smell and how we should take care of it. In schools, we talk about the anatomy of your organs, but we don’t talk about the best way to take care of your menses, what type of pain is normal, what is not normal and all these things,” she says. “We don’t talk about it because there’s still a stigma around it.”

According to Forbes, only about 1% of healthcare research and innovation is invested in female conditions beyond oncology. “There is very little interest to invest in research on women’s health. If we had spent the money that has been spent on erectile dysfunction on developing drugs for BV, we would have them,” says Schuppe Koistinen.

If something doesn’t feel right down there, rather than looking for a quick fix on the internet or seeking advice from influencers, women should talk to a doctor, Gunter says. “People struggle to get the right diagnosis and try all sorts of things,” she says. “I understand that. But I’m also very angry that [some people] take advantage of that.”