What Does a Vaginal Microbiome Test Actually Tell You About Your Fertility?

You've heard about gut health. You've probably got a probiotic in your bathroom cabinet and a kombucha in your fridge. But what about the microscopic world living in your vagina? Yeah, we're going there — because your vaginal microbiome is one of the most important (and most underestimated) parts of your body, and it deserves the same hype. 🙌

Whether you're TTC, dealing with recurring BV, noticing changes in your discharge, or just curious about what's actually going on down there — this one's for you.

📝 In this article:

So... what even is the vaginal microbiome?

Also called your vaginal flora, vaginal microflora, or vaginal microbiota, the vaginal microbiome is the community of microorganisms — mostly bacteria — that live in and around your vagina. Think of it as a tiny, living ecosystem that works around the clock to keep you healthy. 🌿

Every vagina has its own unique microbial balance, but a healthy vaginal microbiome has one major thing in common: it's dominated by Lactobacillus bacteria. These helpful little guys produce lactic acid, which keeps your vaginal pH low (between 3.8 and 4.5), making it an inhospitable place for harmful bacteria to take hold.

Your vaginal biome is different from your gut microbiome in a key way: diversity isn't necessarily a good thing here. While gut health thrives on microbial variety, across many species — humans included — a healthy vaginal environment is dominated by Lactobacillus. These bacteria keep things acidic, hold harmful microorganisms at bay, and help sperm survive long enough to do their thing. [1]

Less Lactobacillus = less protection. It really is that simple (well, mostly).

Lactobacillus vs. Gardnerella: The main characters

If the vaginal microbiome were a TV show, Lactobacillus would be the protagonist and Gardnerella the complicated villain you kind of feel sorry for.

Lactobacillus vaginal species — including L. crispatus, L. iners, L. gasseri, and L. jensenii — are the MVPs of a healthy vaginal microbiome. They acidify your vaginal environment, fight off pathogens, and keep inflammation in check. [2,3]

Gardnerella bacteria, on the other hand, are associated with bacterial vaginosis (BV). When Gardnerella overgrows and Lactobacillus numbers drop, it tips the balance into what's called vaginal microbiome dysbiosis — and that's where things can start to feel (and smell) off. We're talking that fishy odor, grey-white discharge, and general vaginal unease. 😬

This is sometimes also called an imbalanced vaginal microbiome, altered vaginal microbiota, or vaginal flora imbalance — and it's way more common than most people think.

Not all Lactobacillus are the same

Not all Lactobacillus species are equally protective. L. crispatus is generally considered the gold standard, while L. iners is more complicated — it can show up in healthy vaginas, but it's also the strain most likely to be hanging around when things are shifting toward BV — kind of a fence-sitter.. [4,5]

Why your vaginal microbiome could matter more than you think

Here's the thing: the vaginal microbiome is a largely overlooked area of medicine that could dramatically improve outcomes for millions of women, according to a 2025 review co-authored by the UK's Medicines and Healthcare products Regulatory Agency (MHRA). The review found that vaginal microbiome testing could genuinely change the game for women's health — helping catch infections, fertility issues, and even some cancers earlier, and with more precision than current methods allow. [6]

So, yeah. It's kind of a big deal.

While the gut microbiome has received widespread attention over the last decade, research into the vaginal microbiome has lagged far behind. That's partly down to the historic underrepresentation of women in medical research — but the tide is turning, and fast.

Vaginal microbiome and fertility: What the science actually says

If you're TTC — or just thinking about it down the line — pay attention here, because the link between your vaginal microbiome and fertility is pretty significant. 👇

The vaginal microbiome helps keep your pH in check and stops harmful bacteria from taking over — both of which matter a lot when you're trying to get (and stay) pregnant. And it goes even deeper: having the wrong bacterial balance has been linked to poorer egg quality and reduced fertility overall. [1,7]

Research published in Genomics, Proteomics & Bioinformatics suggests that when the microbial balance is off in people of reproductive age, it can lead to a range of pregnancy complications — with real consequences for both the pregnant person and the baby. [8]

And if you're going through IVF? Studies have shown that the mix of bacteria in your vaginal microbiome can genuinely affect how well IVF works — with certain bacterial profiles linked to better implantation and higher pregnancy rates. [1]

Gut health and fertility: The indirect link

Here's something wild: your gut microbiome can actually affect your vaginal health, too. The gut-vaginal axis is real. The gut microbiome can influence the genes involved in sperm production and sex hormone regulation, and research increasingly shows that gut dysbiosis can ripple outward, disrupting hormone balance and inflammation levels that impact reproductive function. [1,9]

So yes — kombucha might be good for your vagina. Indirectly. More on that later. 🍵

Microbiome fertility disruptors: Bacteria that can cause infertility

Not all bacteria are benign passengers. Some can actively work against your fertility goals.

Ureaplasma bacteria is one of the big ones. Ureaplasma is a type of bacteria found in the vaginal and urinary tract that, when levels get too high, has been linked to chronic inflammation, implantation failure, and recurrent pregnancy loss. It's also a concern in the question of whether bacteria in sperm can cause infertility — because yes, ureaplasma can be sexually transmitted and found in semen, potentially affecting sperm quality and fertilization outcomes. [10]

Gardnerella vaginalis, certain strains of Mycoplasma, and other anaerobic bacteria associated with vaginal dysbiosis have also been studied for their potential role in reducing fertility — another reason why it could be worth getting your vaginal biome checked while TTC, particularly if you’ve been trying for a year, or 6 months if you’re over 35. [11,12]

Signs of an imbalanced vaginal microbiome

Not every disruption comes with obvious symptoms — which is why vaginal microbiome dysbiosis is often missed. But common signs include:

• Unusual discharge (gray, white, or yellow)
• Fishy or unpleasant odor (especially after sex)
• Itching or irritation
• Burning during urination
• Recurring BV or yeast infections
• Unexplained pelvic discomfort
• Infertility (unable to get pregnant after 12 months)
• Recurrent pregnancy loss

If any of this sounds familiar, it's worth talking to a healthcare provider — and potentially looking into vaginal microbiome testing.

But one thing we've heard from members of the Peanut community is just how surprising vaginal microbiome testing can be. Some people discover significant dysbiosis despite having no classic BV symptoms — no fishy odor, unusual discharge, or obvious signs that anything is wrong. Others have spent years TTC or navigating recurrent pregnancy loss before learning that high levels of Gardnerella and other BV-associated bacteria may be part of the picture. That’s not to say that dysbiosis is the main reason for unexplained infertility, but it’s one (of many) things that could be worth looking into. [13]

Vaginal microbiome and miscarriage: Is there a link?

Miscarriage sadly affects around one in five pregnancies, and while research suggests that around half can be explained by chromosomal issues in the embryo, millions of losses have no clear cause. Researchers are increasingly looking at the vaginal microbiome for answers — and what they're finding is compelling. [14,15,16,17]

A 2022 study funded by Tommy's found that women who miscarried despite having a chromosomally healthy embryo had significantly lower Lactobacillus levels than women who delivered at term. They also had higher levels of bacteria like Prevotella and Streptococcus, which appeared to trigger an inflammatory response that may interfere with early pregnancy. Studies of recurrent miscarriage tell a similar story — lower Lactobacillus, higher levels of disruptive bacteria like Gardnerella and Ureaplasma, and more inflammation overall. [17,18]

The science is still evolving, and researchers are clear that the vaginal microbiome is just one piece of a complex puzzle. But the idea that an imbalance — one that's potentially detectable and treatable — could be contributing to unexplained pregnancy loss is a genuinely hopeful direction.

What throws off your vaginal microbiome?

So many things can disrupt the microbial balance for feminine health — some obvious, some genuinely surprising:

• Antibiotics are a big one. They're lifesavers, but they're not selective — they wipe out Lactobacillus along with the bad guys, leaving the door open for opportunistic bacteria like Gardnerella to take over. [19]
• Hormonal changes matter, too. Your menstrual cycle, pregnancy, perimenopause, hormonal birth control — all of these shift estrogen levels, which directly affects which bacteria thrive in your vaginal environment. [20]
• Sexual activity can change your vaginal pH, especially when semen (which is alkaline) enters the picture. New sexual partners can also introduce different bacteria, temporarily shifting your microbiome. [21]
• Scented soaps, douching, and fragranced products used on or near the vulva are a classic culprit. Your vagina is self-cleaning. The soaps don't help. They disrupt the natural normal urogenital flora and can trigger BV or yeast infections. Step away from the vaginal deodorant.
• Diet and lifestyle also play a role. High sugar intake, chronic stress, smoking, and lack of sleep have all been associated with a less-than-ideal vaginal microbiome. What you eat and how you live shows up down there. [22]
• Tight synthetic underwear and wet gym wear create the warm, moist conditions that let unhelpful bacteria flourish. Breathable cotton is genuinely your vagina's best friend. 👗

Your partner’s microbiome matters, too

If you're dealing with recurrent BV or fertility issues, it's worth considering that the vaginal microbiome doesn't exist in isolation. Research increasingly suggests partners can exchange bacteria, and in some cases evaluating both partners may be helpful, although more research is sorely needed. [23]

Here's something that doesn't get talked about nearly enough: people with penises can carry higher levels of BV-linked bacteria — including Gardnerella, Mycoplasma, and Ureaplasma — without having a single symptom. Why? Because BV is a condition that affects the vaginal environment specifically, so those without a vagina simply don't experience it. No symptoms, no reason to get tested, no idea anything is going on. But during sex, those bacteria can be transferred — and for someone with a vagina already working hard to maintain their microbial balance, that incoming load of disruptive bacteria can be enough to tip things out of balance all over again.

And it's not just about what those bacteria do to the vaginal environment — they can affect sperm health directly, too. Research has linked bacteria like Ureaplasma and Mycoplasma in the male reproductive tract to increased sperm DNA fragmentation — essentially, damage to the genetic material carried inside sperm cells. High levels of DNA fragmentation can reduce the chances of fertilization, affect embryo quality, and have been associated with recurrent pregnancy loss. So if you're TTC and struggling to get answers, sperm DNA fragmentation testing is worth raising with a fertility specialist — especially if standard semen analysis has come back "normal" but something still doesn't feel right. Normal sperm count and motility don't tell you anything about the integrity of the DNA inside those sperm. [34,35]

This isn't about blame — not even a little bit. It's just biology, and it's genuinely useful information. If you're dealing with recurring BV or unexplained fertility struggles, it may be worth both partners getting tested for bacteria like Ureaplasma and Mycoplasma. The good news is that treatment options for partners with penises are similar to those for people with vaginas — antibiotics or antimicrobials to clear problematic bacteria, and probiotics to support a healthier microbial environment going forward. Testing and treating both partners at the same time is often the most effective approach.

Vaginal microbiome and ovarian cancer: What we know so far

The emerging research here is genuinely fascinating — and a little sobering. Scientists are beginning to investigate whether the vaginal and reproductive microbiome could play a role in the development of gynecological cancers, including ovarian cancer. A new MHRA-supported review highlights that vaginal microbiome diagnostics could potentially support earlier detection of gynaecological cancers — offering a non-invasive window into conditions that are notoriously hard to catch early. [6]

One of the most striking findings comes from a UCL study funded by The Eve Appeal, which found that women diagnosed with ovarian cancer had significantly fewer protective Lactobacillus bacteria in their vaginal microbiome. The same pattern was seen in women carrying a BRCA1 gene alteration — which comes with a 40 times higher lifetime risk of developing ovarian cancer. Researchers believe that when Lactobacillus levels drop, it allows potentially harmful bacteria to migrate upward through the reproductive tract toward the fallopian tubes — which is where the most common and aggressive form of ovarian cancer is thought to originate. [21]

Researchers are now exploring whether cervicovaginal microbiome profiling — a simple, non-invasive swab — could one day be used alongside existing markers to help identify women at higher risk, long before symptoms appear. We're not there yet, but watch this space. [24,25]

How to reset your vaginal microbiome naturally

Good news: you don't need a total overhaul. Small, consistent changes can meaningfully shift your vaginal microbiome over time. But microbiome restoration often isn't linear, and meaningful improvements can take weeks or months.

Foods that support vaginal microbiome health

What you eat genuinely affects what grows down there. Fermented foods — think yogurt with live cultures, kefir, kimchi, sauerkraut, and yes, kombucha — introduce beneficial bacteria that can support both gut and vaginal health. Fiber-rich foods feed the good gut bacteria that in turn support hormonal balance and systemic inflammation levels.

Foods high in vitamin C (think citrus, bell peppers, leafy greens) help maintain a healthy acidic vaginal environment. And staying well-hydrated keeps your mucous membranes (including vaginal tissue) functioning as they should.

What to cut back on? Refined sugar, alcohol, and highly processed foods — all of which can promote bacterial and yeast overgrowth.

Vaginal microbiome supplements: Do they actually work?

The probiotic market is booming, but not all supplements are created equal. Probiotics are live bacteria (and sometimes yeasts) that support your health — and while most people associate them with gut health, research into what they can do for your vaginal microbiome is growing fast. The science is still catching up, but it's looking promising. [26,27]

The best probiotics for vaginal health are those containing strains specifically shown to colonize and support the vaginal environment. Look for probiotic strains for vaginal microbiome balance that include:

• Lactobacillus crispatus: The gold standard for vaginal health, the most protective strain
• Lactobacillus rhamnosus (GR-1): Well-studied for BV prevention
• Lactobacillus reuteri (RC-14): Often paired with GR-1 for vaginal microbiome support

What about antimicrobials?

Sometimes probiotics alone aren't enough — especially if disruptive bacteria like Gardnerella or Ureaplasma have already taken hold. In those cases, your healthcare provider might recommend an antimicrobial to help clear things out before rebuilding with probiotics.

Here's the thing though: traditional antibiotics, while sometimes necessary, can be pretty indiscriminate. They don't just target the bad guys — they can wipe out your protective Lactobacillus in the process, which can make it harder to rebalance afterward.

That's why some clinicians are now turning to targeted antimicrobial options that are gentler on the good bacteria. Products like MicroClear are sometimes recommended as part of a broader protocol to address dysbiosis without nuking your entire vaginal ecosystem.

That said, this isn't something to self-prescribe. Antimicrobials — even the less aggressive ones — should always be taken under the guidance of a healthcare professional who's reviewed your microbiome results. What works for one person's bacterial profile might not be right for another's.

Don’t forget about biofilms

Some BV-linked bacteria can form biofilms — basically protective shields that help them stick around and dodge antibiotics. It's one reason BV can be so frustratingly persistent even after treatment. [28]

So how do you actually tackle them? This is where biofilm-disrupting strategies come in — and it's an area that's getting a lot of attention in vaginal health circles right now.

Some practitioners recommend combining antimicrobials with specific biofilm-busting approaches, such as:

• BioDisrupt: A targeted supplement designed to break down the protective matrix that BV-linked bacteria hide behind, making them more vulnerable to treatment. [29]
• NAC (N-acetyl cysteine): A naturally occurring compound that has shown promise in disrupting bacterial biofilms and supporting the body's own defenses, with some early research suggesting it may help reduce BV recurrence when used alongside standard treatment. [30]

Neither of these is a magic bullet on their own, and the research — while encouraging — is still developing. More importantly, they're not supplements to throw at the problem without guidance. If you suspect biofilms are why your BV keeps coming back, that's a conversation to have with your healthcare provider before adding anything new to your routine. A clinician who's familiar with vaginal microbiome testing can help you figure out whether a biofilm protocol makes sense for your specific situation. 🙏

Daily routines for vaginal microbiome health

How you maintain a balanced vaginal microbiome every day is just as important as any supplement:

• Wear breathable, cotton underwear and change out of wet clothes promptly
• Avoid douching — your vagina cleans itself
• Use unscented, pH-balanced products for external cleansing only
• Pee after sex (even TTC sex) to reduce the risk of urinary tract infections
• Manage stress — chronic cortisol disrupts hormone balance and microbiome composition [31]
• Get enough sleep — 7–9 hours supports immune function and microbial stability [32]
• Support your gut — a healthy gut microbiome is genuinely connected to vaginal microbiome health [33]

What is vaginal microbiome testing?

Vaginal microbiome testing (sometimes called a vaginal microbiota test) involves collecting a vaginal swab — usually at home — and sending it to a lab for advanced analysis. Unlike traditional swab tests that only look for specific pathogens, microbiome tests use next-generation sequencing to map the full bacterial landscape of your vagina.

This means you get a detailed picture of which bacteria are present and in what proportions, whether your Lactobacillus levels are protective, whether potentially disruptive bacteria like Gardnerella, Ureaplasma, Mycoplasma, or anaerobes are present, and what your vaginal pH profile looks like.

How to choose a vaginal microbiome test

When looking at what's out there, prioritize tests that:

• Use 16S rRNA sequencing or metagenomics — these are the most thorough and accurate DNA analysis methods available, and they give you a much fuller picture than standard swab tests
• Provide clinician-reviewed results, not just a raw data dump
• Include actionable recommendations based on your specific profile
• Are from accredited labs with clinical validation

Companies like Juno Bio, Evvy, Regenerus Labs, and Fertilysis offer at-home vaginal microbiome testing that ticks many of these boxes — with varying levels of clinical follow-up included. Always check what's included in the price and whether a healthcare provider reviews your results.

Can a gynecologist do a microbiome test?

Short answer: kind of, but probably not the full picture you're looking for.

Your gynecologist can take a vaginal swab and test for specific bacteria — like Gardnerella (linked to BV), Ureaplasma, or STIs. These are standard diagnostic tests available through most clinics.

What most gynecologists can't currently offer through a routine appointment is a comprehensive vaginal microbiome sequencing test — the kind that maps your entire bacterial ecosystem. That level of testing typically needs to go through a specialist lab, and it may not be widely available through mainstream healthcare yet.

That said, always loop in your doctor or gynecologist when interpreting results, especially if you're TTC or managing a reproductive health condition. Microbiome data is a tool, not a diagnosis.

Is vaginal microbiome testing worth it?

For some people? Genuinely, yes. For others? Maybe not right now.

Vaginal microbiome testing is worth considering if you have recurrent BV or yeast infections that keep coming back, if you're TTC and want to optimize your reproductive environment, if you've experienced IVF failures or recurrent early pregnancy loss, if you've been treated for ureaplasma and want to confirm clearance, or if you simply want to understand your baseline and proactively support your health.It's less urgent if you have no symptoms, no fertility concerns, and a gynecologist who's already keeping an eye on things.

Ultimately, your vaginal microbiome is doing a lot — protecting you from infections, supporting your fertility, potentially guarding against more serious conditions — and it deserves the same attention you give the rest of your health. The science is still growing, but the direction is clear: what lives in your vagina matters more than we ever realized.

Whether you're looking to improve your vaginal microbiome naturally, considering testing, or just trying to understand why things feel off down there, you're not alone — and you're asking the right questions. 🙌

The Peanut community is full of women navigating exactly this. Share your experience, ask your questions, and find your people. 🥜