Editor’s note: While we could find plenty of research on body odor and halitosis (bad breath), there was very limited research on vaginal odor, despite it being a very common complaint for women who seek medical care. 

Accuracy and scientifically-sound education is crucial to Evvy, which is why we always link out to sources such as studies from peer reviewed journals and organizations like the CDC in all of our content. But, because there just isn’t much science on vaginal odor, you’ll see citations to other resources in this article, like WebMD and interviews with MDs. This only serves as motivation for us to work towards closing the gender health gap by pioneering vaginal health research that gives people the information about their bodies they deserve. 

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Vaginas are meant to smell like vaginas. Not like scented intimate wash products, pineapple juice, fruit salad, or a rosebush. 

Chances are you already know what “normal” smells like for your vagina, though this probably changes slightly as your menstrual cycle goes through the motions. 

But, sometimes things can smell a bit…off. Maybe stronger, unusual, or abnormally foul. You’re not alone if you’ve rushed to your web browser, and typed in, “Why does my vagina smell like rotten eggs?” or “death” (yes, really). 

Below we share some of the most commonly (and a few more obscure) searched vaginal “smells” and explain the types of vaginal infections, environmental factors, and hormonal shifts they’re associated with including: 

Where does vaginal odor come from?

The origin of vaginal odor is complicated and probably different for every person because when it comes to vaginal odors, multiple factors are at play. 

Simply put, vaginal odor is a combination of smells produced by the byproducts of different microbes within the vaginal microbiome. (Want to test yourself for the types of microbes that may be related to your vaginal odor? Evvy tests for all bacteria and fungi in the vaginal microbiome).  

In fact all body odor originates from the different odors bacteria produce (known as bacterial odorants).

Certain vaginal bacteria release chemicals that are smelly, specifically chemicals called “biogenic amines”. Biogenic amines can cause the vaginal pH to raise. 

Right now, Dialister, Prevotella, Parvimonas, Megasphaera, Peptostreptococcus, and Veillonella are suspected to be responsible for producing most of the smelly molecules, because they have the genes required to produce biogenic amines. 

Certain biogenic amines — Putrescine and Cadaverine — are produced by the microbes that cause BV and smell like rotting meat, or rotting fish—hence the fishy smell associated with BV!  

However, biogenic amines are not the only cause of vaginal odor. Odor is created when the bacteria from the vagina mix with other fluids or bacteria nearby. 

Add discharge, the microbes present in genital sweat, menstrual blood, a sprinkle of urine, and sometimes, trace amounts of feces, into the mix and you’ve got just about everything that makes up vaginal odor.

For example, the microbes in flatulence (and urine), give off Hydrogen sulfide — a bacterial odorant that smells eggy, or rotten. Vaginally, this type of odor can crop up when urine secretions mix with the bacteria from the vagina and anal area. 

You get the picture! Now, onto common vaginal odors:  

@evvybio Like for pt. 2 #vagtok #evvy #womenshealth #bacterialvaginoisis #yeastinfection #aerobicvaginitis #trichomoniasis #femininehygiene #vaginosisbacteriana #vaginosisbacterianavscandidasis ♬ original sound - 🎃🎸

Types of vaginal odors and what they can mean 

Earthy, ripe or musky vaginal odor

While there’s no one signature odor for a healthy vagina, it’s common for people to describe theirs as smelling “earthy”, “pungent” or even “musty.” 

A slightly stronger version of your vagina’s usual odor is typically nothing to worry about. The types of bacteria shift when your hormones shift throughout the menstrual cycle, which can change the smell of your vagina, alongside your vaginal pH. Towards the end of your period, this earthy smell might be more noticeable. 

Trapped sweat can contribute to an earthy odor, too! So after a workout you’re more likely to notice a pungent, earthy vaginal scent—herbaceous even, a bit like clary sage. This is especially true when wearing moisture wicking underwear, or gym shorts/leggings that are designed to wick moisture away from the skin. 

If you get a whiff of this herby blend, it’s probably just genital sweat. 

BO or onion-like vaginal odor

The vulva has two types of sweat glands. The eccrine glands typically secrete moisture that doesn’t smell like anything while the apocrine glands have oily, stronger smelling secretions because they mix with bacteria on the skin. 

Fun fact: there are lots of apocrine glands in our hair follicles, like our pubic hair! So when we sweat (for any reason, not just when working out), our vulva can smell like an intensifying of that earthy odor that may resemble the smell of general body odor or onion. 

When jumping around during a workout (or just when out and about, doing daily activities) we can release discharge, and even small amounts of urine. So, a mixture of genital sweat, discharge and urine can cause a stronger, slightly unpleasant musky odor that might resemble general B.O. 

Btw, that is not an endorsement to try vaginal deodorant. Feminie hygiene products can be harmful to your vaginal microbiome and even increase your risk for infections like bacterial vaginosis. 

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Rotten vaginal odor (or like eggs)

Okay, we’ll just go ahead and say a lot of us have been here. While unpleasant it’s not anything to be mortified about, nor is the smell of death and decay (the name of a real perfume, courtesy of Lush) wafting out from your vagina a commentary on your personal hygiene habits. 

This is likely your vagina’s way of telling you: hey you, something is up down here! 

Let’s go over what could be happening:

Aerobic vaginitis 

 When it comes to vaginal scents, aerobic vaginitis is strongly associated with a pungent, rotting vaginal odor.  Like BV, Aerobic Vaginitis is also caused by a decline in Lactobacillus dominance of the vaginal microbiome and an elevated pH. This gives way to an overgrowth of aerobic bacteria, typically E.coli, Staphylococcus aureus, group B Streptococcus (GBS), and Enterococcus faecalis which need oxygen to multiply, unlike BV, which is caused by anaerobic bacteria.

The long-lost tampon 

A forgotten tampon can also produce a rotting smell. 

This odor will get stronger the longer it’s up there, as bacteria that thrive on bloody surfaces multiply. There’s a greater risk of toxic shock syndrome (TSS) — a rare but potentially fatal condition where bacteria spreads through the body, releasing harmful toxins — when a tampon is left in the vagina over six to eight hours. TSS is a risk even with fancy and organic tampons, or menstrual cups. 

It’s important to note that some experts and research have suggested that changing tampons too frequently, may introduce excessive amounts of oxygen into the vagina, notably because “oxygen is required for TSS toxin production.” 

So, change your tampon in moderation, in line with guidelines and according to your menstrual flow. You should always use the lowest absorbency tampon you can manage comfortably. And remember, if in doubt, read the back of the box.

Menstruation 

A milder form of this decay type smell, can crop up when you’re menstruating too, as blood and tissue pick up bacteria as they pass out the vagina.

Fishy, meaty, or cheesy vaginal odor

Many people with vaginas experience a smell that resembles food that comes from a farm or the ocean. 

This may feel strange when you think about the fact that these odors are coming from your vagina, but it’s normal for certain microbes to give off scents we associate with fish, meat, or cheese—remember, they contain bacteria too!   

Bacterial vaginosis

The microbe that primarily causes BV — G.vaginalis — produces specific chemicals that make a strong fishy, or even rotting fish, like odors. These include: 

A 2002 study into TMA levels in vaginal secretions of women with BV, found TMA in all participants with high bacterial diversity (Nugent scores between 7 and 10). It wasn’t found at all, or only in small amounts, in women with Lactobacillus dominant microbiomes (Nugent scores between 0 and 3).

Trichomoniasis 

A fishy odor could also be a symptom of Trichomoniasis, an STI caused by a parasite, not a bacteria, called Trichomonas vaginalis. 

The digestive system and urogenital tract 

Less commonly, a fishy vaginal smell can also be associated with conditions that aren’t infectious like urinary incontinence, malignant ulcers, trimethylaminuria or chronic constipation. 

More than one study has found that some types of gut bacteria, ramp up Trimethylamine (TMA) production, a chemical that makes a fishy odor. These include Anaerococcus, Providencia, Edwardsiella, Clostridium, Collinsella, Desulfovibrio, Lactobacillus and Proteus. 

Semen, sex, and inflammation

Because the pH of semen is naturally higher than an ideal vaginal pH, it can temporarily shift the pH of the vagina. This can give way to a fishy, meaty or cheesy smell, too. 

A sulfury, chicken-like odor is also linked to sweat’s interaction with skin bacteria. This may be more noticeable after sex, because you’ve just got hot and sweaty. 

Bleach or ammonia vaginal odor

Discharge and sweat 

Small amounts of urine mixed with discharge, or sweat, can give vaginal odor an ammonia, or urine-like tang. 

Using menstrual pads or tampons 

When using menstrual pads or tampons, traces of urine are absorbed, along with blood, which can trigger an ammonia odor, too. 

Lubricants and condoms 

If you notice that this odor shifts towards the smell of bleach, or cleaning products (especially after sex), some OB-GYNs suggest lubricants and condoms might be the culprit. 

A sign of bacterial vaginosis 

Though bacterial vaginosis’ signature scent is an unpleasant, fishy odor, sometimes, an ammonia-like vaginal odor can be associated with Bacterial Vaginosis (BV), specifically cases that are caused by an overgrowth of Prevotella bivia. A 1997 study found that when P. bivia was grown with certain nutrients it produced high levels of ammonia, which then enhanced the growth of G. vagnialis.

More rarely, some BV infections can start because fecal microbes from the anal cavity, make their way into the vagina. These fecal microbes produce bacterial odorants that can result in foul odors like ammonia, musty, or rotten eggs.  

Asparagus

While the foods we eat aren’t strongly associated with vaginal odor (again, the pineapple challenge is a scam), the sulfur compounds in asparagus that produce stealthy, unmistakable ammonia odor that you notice when you pee, can also shift your vaginal odor this way too, as traces of urine mix with vaginal secretions. 

Sour, tangy, vinegar/yogurt-like, fermented vaginal odor (or like beer)

On that note, if a bread-like vaginal odor smells more like sourdough less like a  standard loaf, it’s normal and possibly even a good sign! This type of sour, tangy vaginal odor can also resemble any kind of fermented food or beverage, like beer.

A healthy vagina’s acidic environment (where Lactobacillus can thrive, reducing harmful microbes) with a pH between 3.8 and 4.5, produces this pickled or fermented type smell. 

Metallic, tinny, coppery vaginal odor

Menstruation 

Like the back of a spoon, or pennies, a metallic vaginal odor is linked to menstrual blood and blood has a high iron concentration. Light, non-infectious bleeding after sex can amplify this metal, tinny scent too. Unexplained, intermenstrual bleeding might also take on this vaginal odor. 

It’s important to note that this could become increasingly fishy or rotten if bleeding or spotting outside of your period is because of an infection, like an STI, or pelvic inflammatory disease (PID), in which case it’s best to consult a doctor! 

Sweet, citrusy, or bittersweet vaginal odor (like molasses) 

Just genital sweat 

Sometimes, genital sweat will interact with bacteria on the skin to produce a smell resembling tropical fruit, or grapefruit. 

Some of the microbes within a healthy vaginal microbiome can give off molasses-type, earthy odors too! 

What we don’t know about vaginal odor

We’re going to throw one of Evvy’s most frequently used phrases here: there’s a huge lack of research around the variety of vaginal odors and their causes. 

Unless the odor is fishy and the patriarchy is pushing a blatantly offensive and misogynistic narrative that that odor is related to a woman’s hygiene and worth (a la Nick Canon) or if it’s to work out what type of vaginal odors men prefer — ovulation vulva or birth control vulva eau de parfum—we don’t have many answers! 

Let’s face it: science has historically researched our bodies, through the lens of male pleasure, like we’re in a Mad Men episode: regressive, boring, and freudian.

Our advice? Get to know what’s normal for you. 

Slight changes in vaginal odor are normal and expected. But anything that smells deeply unpleasant, strongly fishy, or like rot, death, decay and all other things macabre, needs to be looked at by an OBGYN—stat!  

Interested in testing at home, too? An Evvy test will reveal any imbalances within the vaginal microbiome, down to the types of disruptive microbe and its relative amount. That way, you can compare your odor symptoms with your results. For eligible tests, we also offer prescription treatment programs developed for you by a provider based on your unique microbiome and symptoms like odor.

More than anything, get familiar with your own unique vaginal odor, and how this shifts throughout your cycle. You’ll intuitively know when something is amiss, and if in doubt, refer back to this guide, talk to your doctor, and test, test, test! 

Written by Dr. Meagan Hamblin PhD & Rachel Mantock