BV in Black women: are you more prone?

Author: Jessica Lloyd
Senior Vulvovaginal Specialist Naturopath | BHSc(N) | ISSVD, ISSWSH, BSSM, ATMS

Last reviewed: July 4, 2026

Statistically, yes: bacterial vaginosis (BV) is roughly twice as common in women of African descent as in most other groups, mostly because of naturally lower numbers of protective lactobacilli and a more diverse mix of vaginal bacteria¹.

But the fuller picture is more interesting, and a lot more reassuring, than ‘something is wrong with you’. For a great many Black and Hispanic women, the vaginal microbiome is simply a different normal – more diverse, lower in lactobacilli – and a different normal is not the same as a worse one.

Part of that higher ‘BV rate’ is real biology. Part of it is that our standard BV tests were built around a low-diversity, mostly-white microbiome, so they can flag a perfectly well, diverse community as disease. If you are a Black woman, your vagina isn’t the problem here – it’s an interesting bit of biology worth understanding.

Is BV really more common in Black women?

On the numbers, BV in Black women does run higher. The largest US population survey put overall BV prevalence around 29 per cent, but with a big spread by group: roughly 51 per cent in Black women, 32 per cent in Mexican-American women, and 23 per cent in white women².

Up to 40 per cent of women of African ancestry don’t have a lactobacilli-dominated vaginal microbiome at all, compared with a much smaller share of white and Asian women³. And the gap doesn’t disappear when you account for behaviour – it holds up even after adjusting for things like number of partners, which points to something more innate than lifestyle¹.

One quirk worth holding onto: in the vagina, lots of bacterial diversity is linked to more infections and imbalances, whereas in the gut, diversity is a sign of health.

Lots of different bacteria in the vagina = often a problem
Lots of different bacteria in your belly = usually good

A different kind of normal

Low lactobacilli counts don’t mean an unhealthy vagina. They just mean being more prone to vaginal infections and microbial imbalances – a leaning to be aware of, nothing more.

Researchers sort vaginal microbiomes into five broad community state types. Four are dominated by a single lactobacillus species; the fifth, often called CST IV, is the diverse, low-lactobacilli community that turns up more often in Black and Hispanic women³. Plenty of women carry that diverse community with no symptoms at all and are completely well – it can be one version of a healthy vaginal microbiome.

This is where the testing gets sticky. The traditional ways of diagnosing BV under a microscope (the Nugent score and Amsel criteria) were calibrated on lactobacilli-dominant vaginas, so a naturally diverse-but-healthy microbiome can score as ‘BV’ even when there are no symptoms⁴. It’s one reason different vaginal tests so often disagree. Researchers have openly flagged that this labels an asymptomatic chunk of Black and Hispanic women as ‘less healthy’ than white and Asian women, when the science behind that judgement is far from settled⁴. This is exactly why a positive result deserves context: we unpack whether a ‘BV’ result with no symptoms actually means you’re unwell.

There’s a deeper issue worth naming here. When the yardstick for a ‘normal’ microbiome is built around a mostly-white one, a Black woman’s perfectly healthy version gets measured against someone else’s and labelled abnormal. It’s another way Black women can be quietly othered by the medical system – their own normal treated as a problem to fix.

So if you’ve been told you have BV but feel completely fine, it’s worth knowing that a swab can over-call it – and that the right thing to treat is symptoms and genuine imbalance, not a number on a lab report.

How you get your vaginal bacteria in the first place

As a baby comes out of the vagina, its nose and mouth – and if it’s a girl, its vulva – get coated in the mother’s vaginal bacteria. That’s our very first set of bacterial colonies, and it sets the early template (until something shifts it, like antibiotics).

From there, ancestry seems to do a lot of the steering. Women with African or Hispanic maternal lines tend to carry far fewer lactobacilli than women from other backgrounds, and the research suggests this is a natural difference rather than anything about behaviour¹.

We now know your own genes help shape which bacteria settle in and thrive – the species that dominate, and how stable that community is, are partly heritable⁵. Your genes help shape your vaginal microbiome, which is why your mix tends to line up with where your maternal line is from, ethnically speaking.

Fathers don’t come into it much here – they don’t contribute a great deal to our first microbiome, at least not vaginally. And if you were born by caesarean, you pick up your mother’s microbes in other ways.

Vaginal bacteria by ethnicity

As a very rough sketch of who tends to be lactobacilli-dominant:

Asian – mostly lactobacilli
European – mostly lactobacilli
African – around 60 per cent lactobacilli
Hispanic – around 60 per cent lactobacilli

These are averages across big groups, not a verdict on any individual – your own microbiome is yours. Read more about vaginal microbes around the world.

Why the difference exists at all is partly history. For most of human time we lived in fairly separate groups, and the bacteria we met differed from place to place – the dirt and water in one region carry different microbes from another. There was far less mixing between distant communities, so these patterns settled in and were passed down.

Meet the lactobacilli (and the shapeshifter)

Some lactobacilli are far better than others at colonising the vagina and fighting for its health. The sturdy protectors you want to see are:

Lactobacillus crispatus
L. gasseri
L. jensenii
L. reuteri
L. rhamnosus

One species, L. iners, is the shapeshifter of the group. It’s the most common lactobacillus in women of African ancestry, and it can sit happily in a healthy vagina – but it also turns up in droves during BV, and it seems to help the microbiome flip back and forth between balanced and disrupted states⁶. We dig into its odd habits in oleic acid, L. iners and recurrent BV.

So if you get a test and L. iners comes up, don’t assume you’re sitting on strong protective counts. It’s a less reliable bodyguard than its sturdier cousins.

What low lactobacilli counts mean in real life

Lactobacilli are strong, enthusiastic vaginal warriors. When they’re low, invasions are simply easier – pathogens are opportunistic, and weak defences let them take over.

Picture your country’s secret service lined up in full battle armour, except they’re made of animals instead of people.

If your army is a mixed bag – three blind mice, a cat, a dog and a camel – you’re in for a rough trot when a tiger tries to invade. Your hodge-podge weakling army isn’t beating that tiger easily.

If instead you’ve got a lion, two rhinoceros and a deadly snake, you’ll fare a lot better when the tiger picks a fight. It’s the same with your vaginal bacteria: good fighters like L. crispatus make invasion much harder by the way they work.

Low counts can also be made worse by things that knock your defences about – douching, a course of antibiotics, or unprotected sex with partners carrying disruptive bacteria. Your fighters get overwhelmed far more easily.

What this means for your vagina

This is the part that makes the disparity matter, rather than just being a curiosity. When protective lactobacilli are low and the microbiome tips into BV, the vagina loses some of its natural defences.

BV is linked to a higher risk of picking up sexually transmitted infections, including HIV, and in pregnancy it’s associated with a raised risk of preterm birth and pelvic inflammatory disease⁷. The mechanism is partly the loss of those lactic-acid-producing lactobacilli, which strips away some of the vagina’s natural protection⁷.

None of that is a reason to panic or to start treating a vagina that feels fine. It’s a reason to take real symptoms seriously, to test properly when something’s off, and to support your protective bacteria over time rather than waiting for the next flare.

This is something we come across in our clinical work: someone is told they have BV when they have no symptoms at all. Symptoms are part of how BV is diagnosed, so a ‘BV-pattern’ microbiome on a swab can be a red herring.

Plenty of these women have a perfectly healthy microbiome for them, with no symptoms and no problems, yet they get diagnosed and treated anyway – again and again – when they shouldn’t be diagnosed with BV at all. We also see the flip side, people stuck on the antibiotic loop for genuine recurrent BV, so a lot of our work is simply telling the two apart: who actually has BV, and who has a microbiome that’s just normal for them.

What you can do about low lactobacilli and being BV-prone

You are not stuck with the bacteria you were born with, which is the encouraging bit. We pick up new bacterial colonies all the time, so it’s entirely possible to build up your protective species even if you started low.

This is where natural and functional approaches earn their place, and the evidence backs them. In a randomised controlled trial, women given a live L. crispatus vaginal probiotic after antibiotic treatment had BV recurrence of about 30 per cent at 12 weeks, compared with 45 per cent on placebo⁸. Replanting the right species shifts the odds.

A few things that help, when you’re working to tip the balance back:

Choose a good-quality women’s probiotic that contains several of the sturdy strains above, ideally including L. crispatus.
Feed the protective bacteria. Lactulose selectively feeds protective species, so it pairs well with a source of the right bacteria.
Use vagina-specific microbes, not random ones. Be cautious mixing other probiotics, milk kefir or live yoghurt with lactulose – you can end up feeding a colony of strangers.
Skip the douching and harsh washes. They strip the very bacteria you’re trying to keep.

It’s also worth naming the less glamorous drivers. Chronic stress, low income and tough living conditions are independently linked to higher BV rates, especially for Black women – not because of anything anyone is doing wrong, but because the body’s stress load and living conditions do shape the microbiome⁹. None of that is anyone’s fault, and it’s useful to understand.

Do low numbers of lactobacilli actually matter?

Yes and no. You can have a perfectly well vagina with low lactobacilli – it’s simply what’s normal for you. If things smell like not-much, your periods don’t smell like death, and your discharge is unremarkable, there’s nothing to fix.

Our vaginal microbiomes are complex. Bacteria work together to build the environment they want, and that can be good, neutral or bad for us as their host. It’s entirely possible to have a community that’s low in lactobacilli and higher in potential troublemakers and still have no symptoms at all.

Low protective counts matter most when you’re exposed to pathogens and your defences are down. Things that leave you more vulnerable include:

Low immunity (frequent illness, underlying health problems)
Stress
A low-quality diet
Unprotected sex with partners carrying disruptive bacteria
Regular douching

If you do test properly and it flags an imbalance, you can take it from there with your healthcare provider – and sometimes holding off on treatment and letting the body rebalance is a perfectly reasonable path, especially without symptoms.

Frequently asked questions

Does being more prone to BV mean I did something wrong?

No. A lower-lactobacilli microbiome is largely something you’re born with and inherit through your maternal line, not a result of poor hygiene or behaviour. If anything, over-washing and douching make things worse, not better.

Is it bad to have low lactobacilli?

Not in itself. On its own it’s a leaning toward imbalance rather than a disease, and many women with diverse, low-lactobacilli microbiomes are completely well and symptom-free.

Why does a test say I have BV when I feel fine?

The standard microscope-based BV scores were calibrated on lactobacilli-dominant vaginas, so a naturally diverse microbiome can be scored as BV even with no symptoms. Treat symptoms and genuine imbalance, not a lab number in isolation.

Can I actually change my vaginal microbiome?

Yes. We acquire new bacteria throughout life, and the right protective strains can be encouraged to settle in – a live L. crispatus probiotic, for instance, measurably lowered BV recurrence in a randomised trial. It takes patience and the right species, but it’s very doable.

Are Black women at more risk from BV complications?

Because BV is more common in this group, the downstream risks it carries – higher susceptibility to STIs and, in pregnancy, preterm birth – fall more heavily too. That’s exactly why understanding your own microbiome, and treating real problems properly, is worth it.

Should I treat BV if I have no symptoms?

Often not – and you may not even have BV. Because symptoms are part of the diagnosis, an asymptomatic ‘BV-pattern’ swab can simply be a diverse microbiome that’s normal for you, and treating it can do more harm than good. Pregnancy and certain procedures are exceptions worth discussing with a clinician.

What to do next

If you’re prone to BV, the most useful first step is a clear picture of what’s actually growing. A comprehensive vaginal microbiome test shows you your species and counts, rather than a yes/no BV label.

From there, our free Killing BV guides walk through how to rebuild and protect your bacteria, and if BV keeps coming back, it’s worth understanding why BV keeps returning. You can also chat with Aunt Vadge’s Assistant in the bottom-left of the screen, or book an appointment with one of our naturopaths to work on the underlying picture.

This is general information, not a substitute for personalised medical advice.