What's my vaginal microbiome?

Your vaginal microbiome is associated with everything from recurrent infections to fertility challenges to STI acquisition. Don't worry if you've never heard of it — we'll introduce you.

Every day, your vagina performs the equivalent of modern health miracles.

It can fight off infections, bolster fertility, protect a pregnancy, and possibly even defend against cancer. How?

Meet your vaginal microbiome — a complex ecosystem of bacteria, fungi, and more that lives in your vagina.

But these microbes aren't just hanging out in there: the good bacteria in your microbiome actually play a crucial role in your overall health. Given that the vagina is the structural connection between the outside world and some of our most important reproductive organs, the local microbiome has evolved to serve as a critical layer of protection against pathogens entering our bodies.

Fig 1 -> Lactobacillus acidophilus, a protective vaginal bacteria

How does the vaginal microbiome actually work?

While a variety of bacteria and fungi can exist in the vagina, a type of bacteria called Lactobacilli are the local heroes. Lactobacilli ensure that the vaginal environment is inhospitable for potential pathogens in a variety of ways:

  1. Lactobacilli produce lactic acid that helps keep the pH low and healthy — ideally between 3.8 and 4.5. (Ever taken a vaginal pH test? That's actually a rough metric for how much good bacteria are in your vaginal microbiome.)
  2. Lactobacilli take up space on the vaginal wall, preventing other pathogens from being able to thrive
  3. Lactobacilli produce bacteriocins, which further inhibit the growth of disruptive bacteria
  4. Lactobacilli keep inflammation down in the genital tract

An optimal vaginal microbiome consists mostly of Lactobacilli, but not all vaginal microbiomes are the same.

Research has shown that most vaginal microbiomes fall into one of 5 general categories, sometimes called "Community State Types” (CSTs).

Four of the types are dominated by a specific species of Lactobacilli:

  • Lactobacillus crispatus (Type 1)
  • Lactobacillus gasseri (Type 2)
  • Lactobacillus iners (Type 3)
  • Lactobacillus jensenii (Type 5)

Type 4s don't have a dominant species of Lactobacilli. While research on the types is evolving, testing for your type can help you better understand your symptoms and health outcomes.

The DL on dysbiosis

A lack of Lactobacilli in your vaginal microbiome can give pathogens an opportunity to colonize. If and when they do, that's referred to as vaginal dysbiosis. In a state of dysbiosis, there is a high diversity of various types of bacteria, which can allow disruptive microbes like Gardnerella, E.coli, or Mycoplasma to flourish. These bacteria can then cause unwanted symptoms like itching, burning, irritation, or pain, as well as catalyze vaginal infections like bacterial vaginosis (BV), yeast infections, and urinary tract infections (UTIs).

Fig 2 -> Bacteria on the vaginal wall

Are yeast infections, UTIs, and bacterial vaginosis (BV) related to my microbiome?

Yes! The fungi and bacteria that cause vaginal infections are all part of your microbiome. When your microbiome is imbalanced, it creates opportunity for these bad microbes to thrive.

The most common vaginal infection is bacterial vaginosis (BV), which is defined by high bacterial diversity and an abundance of disruptive bacteria. One in three women will get BV each year, and up to 84% of these cases are asymptomatic. In addition, BV disproportionately affects Black and Hispanic women, with disappointingly lacking research as to why (that's what Evvy's here to change!)

Dysbiosis of the vaginal microbiome can also catalyze other types of infections, such as aerobic vaginitis (AV) and cytolytic vaginosis (CV), many of which can have frustrating (and confusingly similar) symptoms, such as itchiness, abnormal discharge, and burning.

What other conditions are associated with the vaginal microbiome?

To add to the many reasons the vaginal microbiome deserves more attention: recent research has uncovered groundbreaking insights on the vaginal microbiome’s role in female health far beyond the vagina.

When the vaginal microbiome is in an optimal state, it can do amazing things. It turns out that having protective bacteria like Lactobacilli in your vaginal microbiome can protect you from a variety of other potential health outcomes.

Research has shown that the composition of your vaginal microbiome is associated with your risk for the following conditions:
  • STIs such as chlamydia, gonorrhea, trich, herpes, HPV, and HIV
  • Pelvic inflammatory disease
  • Fertility issues or failed IVF cycles
  • Pregnancy complications such as miscarriage, preterm birth, neonatal problems, and preeclampsia
  • Gynecological cancers such as ovarian, cervical, or endometrial cancer
  • Cervicitis
  • Toxic shock syndrome

On the flip side, disruptive microbes can create a favorable environment for other infectious microorganisms, increase inflammation, and inhibit your immune response.

An Evvy kit laid out on a table

Caring for your vaginal health starts with understanding the balance of your microbiome.

Meet our vaginal health test

Wait… if my vaginal microbiome is so powerful, why haven’t I heard of it?

Microbiome research is a relatively new field, and lots of resources have been invested in understanding other human microbiomes like the one in your gut or on your skin. But when it comes to your vagina, the microbiome has been overlooked.

We wish the reason why wasn’t yet another gender gap… but that’s why we’re here!

Evvy exists to use cutting-edge research techniques to elevate the vaginal microbiome to its rightful place in research and clinical care, all while providing you with critical insights into your health.

So how can I check in on my own microbiome?

Well — that’s the other reason why we exist.

Evvy’s first product is the first-ever at-home test to leverage metagenomic sequencing to help you understand and strengthen the defense of your vaginal microbiome.

By keeping tabs on its composition, you can catch potential imbalances early, giving you the chance to proactively take action to promote the protective bacteria and prevent the disruptive bacteria from taking hold.

Fig 3 -> We're looking to close the gender health gap (in addition to empowering women with information on their vaginal microbiome.)

How often do I need to check in on my vaginal microbiome?

The vaginal microbiome is critically important to female health and it's also always changing.

Unlike genetic results, which are static, microbiomes are dynamic and can reflect progression towards or away from disease.

There are multiple reasons that the vaginal microbiome changes over time. Your day to day behaviors — such as new birth control, medications, supplements, sexual partners, smoking, stress, or vaginal products — can influence its composition. The vaginal microbiome is also affected by hormones, pregnancy, sex, and menopause.

Given its dynamic nature, if your vaginal microbiome isn’t in an ideal state, it might be cause for consideration — and potentially care — but not concern.

You’ve convinced me my microbiome is important...how can I take care of it?

Here’s the thing about vaginas: they’re pretty great at taking care of themselves. They’re self-cleaning and normally self-protecting, as long as the vaginal microbiome is in balance.

However, many of the things we enjoy — sex and sugar, for example — are good at throwing off this balance.

Plus our bodies naturally change over time, and trying new birth control, medications, sexual partners, period products, and more can add chaos to this balancing act.

Fig 4 -> Different treatments, medications, and supplements can affect your vaginal microbiome

There are some all-around great things you can do to take care of your vaginal microbiome — and we’re pretty sure you’ve heard them before: Drink water, never douche, wear cotton underwear, pee after sex, cut down on sugar, change out of wet swimsuits as soon as you can, the list goes on.

But surprise! Not all vaginas are the same. What works for you might not work for your sister or your friend.

The best way to care for your unique microbiome is to first understand what your microbiome looks like (what bacteria are present) and whether or not it is optimally balanced (psst...that’s what we made Evvy's Vaginal Health Test for!)

And when you do intervene (try a new probiotic, change your diet, etc.),  We'll take the guesswork out of figuring out which solution is working for you. By retesting, you can see how changes you’re making in your diet, life, and supplements are impacting your vaginal microbiome’s defense.

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Gardnerella vaginalis
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