How to Avoid Yeast Infections: Take Care of Your Vagina’s Microbiome

Written by: the Editors of goop


Updated on: November 14, 2022

How to Avoid Yeast Infections: Take Care of Your Vagina’s Microbiome

Photo courtesy of Patrick Van Der Elst

While gut is the microbiome du jour, where all the sexy science is happening, each part of our body with a bacterial and fungal population (i.e., all of them) has a microbiome of its own in careful homeostasis. And if you’re ever acutely aware of one of these other microbiomes, it’s probably because something is wrong.

Take your vagina. Your vaginal microbiome isn’t typically anything to think about…until you get a yeast infection. And then another yeast infection. And then, lucky you, another yeast infection.

More research needs to be done to determine exactly how common recurrent vaginal infections really are, but it is often estimated that three in four women experience a yeast infection in their lifetime and that nearly half of those women will have two or more. And even more common: bacterial vaginosis, another infection linked to vaginal microbiome disruptions.

But many vaginal microbiome infections are preventable if you commit to proper vaginal care, according to Leah Millheiser, MD, a gynecologist and the director of Stanford’s Female Sexual Medicine program. The good news: Most of the time, that means doing absolutely nothing. The bad: You may have to reconsider that habit of living in your yoga pants.

A Q&A with Leah Millheiser, MD

So the vagina has a microbiome. Why does it matter?

I refer to the vagina—and you’ve probably heard this before—as a self-cleaning oven. There are many different types of bacteria and fungi in the vagina that are natural and normal, and those make up the vaginal microbiome. And whenever there is an imbalance in that microbiome—meaning you have an overgrowth of one type of your normal bacteria or fungi, which can happen for many different reasons—you may get a naturally occurring vaginal infection. For example: If you have an overgrowth of yeast, you may have a yeast infection.

Also, a disrupted vaginal microbiome—really, the related infections, like bacterial vaginosis—can make you more prone to sexually transmitted infections like chlamydia, gonorrhea, and HIV.

What does a normal vaginal microbiome look like?

There’s no way to qualify what’s “normal.” There’s no test that says, “Yes. You have the right amount of so-and-so bacteria.” Each woman is different, and each woman’s vaginal microbiome is unique. So whether a woman’s vaginal microbiome is healthy comes down to whether she’s experiencing symptoms. And those symptoms can be itching, a change in odor, pain during intercourse, abnormal discharge…those are subtle ways a woman could detect a change. We really don’t act on that unless she’s developed symptoms that are obviously bothersome to her.

“There’s no way to qualify what’s ‘normal.’ There’s no test that says, ‘Yes. You have the right amount of so-and-so bacteria.’”

What are some common infections to watch out for?

When you notice a foul-smelling or a fishy vaginal odor, that could be a sign of an overgrowth of one of our bacteria called Gardnerella. When your population of Gardnerella overpowers that of Lactobacilli, it disrupts the acid-base balance in the vagina and the pH becomes basic. The pH of a healthy vagina is acidic. When the pH is basic, you start to see symptoms of bacterial vaginosis, including a fishy vaginal odor that women may notice more prominently during their period and after sexual intercourse when a man ejaculates inside of them. Many women notice having copious greyish discharge. They may have a little irritation.

Yeast infections are another overgrowth condition. These occur when you get overgrowth of your normal candida. Everybody has candida in their vagina, but an infection happens when that fungus overpowers others, which can happen for a number of reasons.

There are some typical things I hear when a woman comes to see me for vaginal microbiome-related problems: “I have burning.” “I have itching.” “I have a smell.” “I have an abnormal discharge that I’ve never had before.” Or maybe they come in because they say, “Well, sex is all of a sudden really painful.” And I find that they have a yeast infection or bacterial vaginosis. If you notice those symptoms, see a gynecologist so you can get the right treatment.

What can disrupt the microbiome and cause infections and overgrowths?

So any time women start to put things inside of the vagina—even gentle soaps—that can change its microbiome. Here are some more things to be aware of:

  1. Spermicides. Certain spermicides, like the spermicidal jelly nonoxynol-9, can potentially cause disruptions.
  2. Douching. People may douche because they notice an odor, or they may want to be clean and they think that douching will help them feel that way. However, douching can disrupt your natural vaginal microbiome and, because of that disruption, can actually make you more susceptible to vaginal infection.
  3. Perimenopause and menopause. If you’re older, being peri- or postmenopausal can lead to disruptions because decreased estrogen in your system can actually change the makeup of the cells in your vagina. And it can make the vaginal pH more basic—potentially leading to infections like bacterial vaginosis or increased incidence of yeast infections.
  4. Antibiotics. A lot of people already know that if you’re taking oral antibiotics, you’re more susceptible to a yeast infection—because, again, it’s changing the makeup of the vaginal microbiome.
  5. Immunosuppression. When you’re immunosuppressed for whatever reason, you don’t necessarily have the defense cells that you need to fight infection, and so you may become more prone to vaginal infections. And we start to see yeast infections more often.
  6. Diabetes. Having poorly controlled diabetes can do it, and that’s due to chronic elevation in blood sugar. Yeasts thrive on sugar. That’s one of the foods that keeps them going and makes them reproduce and grow. And so the higher your blood sugar typically is, the more prone you are to vaginal microbiome disruptions and getting yeast infections.

People used to think that the birth control pill could cause these disruptions. Looking at more recent data, however, we know that’s not true. There’s no evidence that tampons cause problems either.

What can help your vaginal microbiome recover from disruption?

So here’s the problem: There’s not a lot of great long-term data on this. We really need to gather more evidence before we can confidently conclude anything, but right now there are a handful of small studies looking at probiotics specifically made to repopulate the vaginal microbiome.

There’s an oral probiotic on the market that you take daily that is focused on promoting a healthy vaginal microbiome. There is some limited research reporting that if you take these probiotics, it can help with the repopulation of those healthy bacteria. To know for sure whether that’s true, we need to have studies following more women over a greater length of time. But there is some preliminary data that shows that taking a probiotic that is focused on vaginal health could be helpful for those people who are prone to bacterial infections or yeast infections.

There are some people who say, “If you put yogurt inside of the vagina, that could help.” Certainly people do it, and anecdotally you hear patients say it helps them, but there really isn’t enough data out there to say that is unequivocally true and it works. We don’t recommend that at this point.

What lifestyle factors play into keeping your vaginal microbiome healthy?

So many women, at least in the US, walk around in yoga pants all day—even after they work out. That is what yeast love: warm, dark, moist areas. That’s where they flourish. It’s a near-perfect setup for infection.

After you work out, change your clothes. Put on dry clothing. Especially if you are prone to getting yeast infections. If you’re not working out and you’re just at work or doing a lot of walking around during the day, it can be smart to take an extra pair of underwear with you in your bag and change underwear in the middle of the day. Sweaty, moist underwear can lead to that environment that makes yeast grow. It’s the same for bathing suits. Changing can provide some extra protection.

“Your vagina doesn’t need anything meant for ‘cleaning.’”

Avoid using anything, like douches or vinegar or steaming, inside of the vagina. Your vagina doesn’t need anything meant for “cleaning.” Your vagina, as I said before, is a self-cleaning oven that will regulate itself. If you are noticing an abnormal odor or abnormal discharge, you need to have that evaluated by your clinician to make sure that you’re not covering up the smell of an actual infection that requires treatment.

Something like an oral probiotic may be effective. We don’t currently have enough research to know for sure, but it’s possible, and so we do recommend them for those prone to recurrent infections.

Leah Millheiser, MD, is a gynecologist, a clinical assistant professor of obstetrics and gynecology, and the director of Stanford’s Female Sexual Medicine program. In her practice at Stanford, Millheiser focuses on women’s sexual well-being, sexual education, and menopausal health care.

This article is for informational purposes only, even if and to the extent that it features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice. The views expressed in this article are the views of the expert and do not necessarily represent the views of goop.