What causes bacterial vaginosis and how to treat the bacterial vaginosis smell?

Bacteria are the guardians of female health, but if this ecosystem gets out of whack, it can cause bacterial vaginosis. Here’s what you need to know about vaginal health, microbes, and recurrent bacterial vaginosis.

You might already know about the gut microbiome (the trillions of bacterial cells in your large intestine that help keep you healthy), but you might be surprised to find out that there is also a vaginal one.

The vaginal microbiome is dominated by bacteria (especially, Lactobacillus), as well as some yeasts and viruses. Usually, these communities are happy and balanced, but sometimes opportunistic can take advantage and grow out of control, causing bacterial vaginosis (BV).

Table of contents

• What is bacterial vaginosis?
• Bacterial vaginosis symptoms
• Recurrent bacterial vaginosis
• What causes bacterial vaginosis?
• Health risks linked to BV
• Bacterial vaginosis testing
• How to treat bacterial vaginosis

Bacterial vaginosis is still a bit of a mystery to the medical community, especially since half of the women with BV do not experience any symptoms at all. Here are the facts on what causes bacterial vaginosis and bacterial vaginosis smell, how it is diagnosed, and common treatments.

☝️DISCLAIMER☝This article is for informational purposes only. It is not intended to constitute or be a substitute for professional medical advice, diagnosis, or treatment.

What is bacterial vaginosis?

Bacterial vaginosis is a condition caused by an overgrowth of some bacteria naturally found in the vagina that is common for women of reproductive age (usually aged 14–44). It is not to be confused with thrush, which is caused by an overgrowth of microscopic yeasts.

☝️FACT☝️Non-bacterial vaginosis is caused by a yeast overgrowth. Doctors can tell whether it’s bacterial vaginosis or thrush by a simple swab test and your symptoms.

Symptoms of bacterial vaginosis

Many women will never know that they have had a bout of bacterial vaginosis because they are asymptomatic (i.e., having no symptoms). Others are cursed with a uniquely fishy odour, also known as the “bacterial vaginosis smell”. Here are the main symptoms of bacterial vaginosis:

• “fishy” vaginal odour
• increased vaginal discharge
• light grey, green, or white vaginal discharge
• intensified odour after sex or during your period

Other more unpleasant symptoms may indicate that you have bacterial vaginitis, a related condition that causes inflammation and pain that is also caused by an overgrowth of opportunistic bacteria. Here are the common symptoms of bacterial vaginitis:

• vaginal itching
• burning sensation when urinating
• spotting

Bacterial vaginosis and bleeding are not commonly found together. If you do experience bleeding outside of your period, or during sex, it could be the sign of something more serious. Don’t suffer in silence, consult your doctor or gynecologist for help.

Recurrent bacterial vaginosis

A healthy vaginal microbiome is dominated by Lactobacillus, probiotic bacteria that keep the pH level balanced. They make lactic acid, providing an acidic environment that deters invaders, like opportunistic bacteria, from growing out of control.

However, some factors can significantly weaken your vaginal microbiome, making you more susceptible to recurring bacterial vaginosis. These include antibiotics, douching, unprotected sex, and multiple sex partners.

Recurrent bacterial vaginosis in pregnancy is also very common. This may be influenced by the fluctuations in hormone levels as the fetus develops and the body prepares for birth. If you have chronic bacterial vaginosis during pregnancy, consult your doctor about treatment.

☝️FACT☝️Three or more proven episodes of bacterial vaginosis in 12 months is considered recurrent. Treatment includes lifestyle changes and antibiotics.

What causes bacterial vaginosis?

A healthy female vaginal microbiome is acidic (pH 3.8–4.5) thanks to a variety of Lactobacillus species: L. crispatus, L. gasseri, L. iners, and L. jensenii. These bacteria produce lactic acid that keeps invaders and opportunistic bacteria in check.

In bacterial vaginosis, there is significantly less Lactobacillus and an overgrowth of other microbes, which upsets the natural balance of the vaginal microbiome. Common bacteria identified in bacterial vaginosis include:

• Gardnerella vaginalis
• Mycoplasma hominis
• Peptostreptococcus
• Prevotella spp
• Mobiluncus spp

Studies primarily indicate that exposing the delicate vaginal environment to external products increases the risk of BV, such as semen and perfumed soaps. However, other less obvious factors come into play too, like diet, antibiotic treatment, and smoking. Common risk factors for bacterial vaginosis include:

Studies show that bacterial vaginosis is most common in women of African and Hispanic descent, and least common in Western European and Asian women. This may be, in part, linked to the large variety of gene variants associated with bacterial vaginosis.

☝️Can you have sex with bacterial vaginosis?☝️ Sex with bacterial vaginosis may worsen the symptoms and be painful.

BV, diet and the gut microbiome

Research into the gut microbiome and diet seems to suggest that they may also influence the risk of bacterial vaginosis. Indeed, Lactobacillus microbes, which dominate a healthy vaginal microbiome, are believed to come from the gut.

Many studies show that taking oral probiotics can support vaginal microbiome health (but you should never put them in the vagina directly).

Plus, a healthy gut microbiome contains beneficial bacteria that produce short-chain fatty acids, which prevent inflammation by keeping the gut lining healthy. If the gut microbiome is unbalanced – a condition called dysbiosis – it can contribute to inflammation, which can spill over and affect the genital tract.

One of the most important factors that influences the gut microbiome is diet. Good bacteria in your large intestine thrive on plant-based foods, vegetables, whole grains, legumes, and fruit. These foods contain prebiotics, special molecules in food that fuel beneficial bacteria.

On the other hand, a Western diet with lots of fast food and simple sugars can encourage the abundance of opportunistic bacteria and reduce levels of beneficial bacteria, like Lactobacillus, and this can have knock-on effects for your health.

Indeed, when the vaginal and gut microbiomes are healthy and happy, their bacteria send positive messages to the immune system, which turns off inflammation. When they’re not balanced, both microbiomes can communicate negative signals to the immune system and encourage inflammation, rather than preventing it.

You can check your gut microbiome with an at-home Atlas Microbiome Test and see if it is making protective short-chain fatty acids. You’ll also get personalised food recommendations to enhance your gut health, which might help the long-term recovery of your vaginal microbiome too.

Risks associated with bacterial vaginosis

A healthy vaginal microbiome helps protect you against infections and inflammation. While BV does not generally present a serious health risk, there are some possible complications you should know about:

Can bacterial vaginosis cause infertility?

There is an indirect link between bacterial vaginosis and infertility. If bacterial vaginosis causes pelvic inflammatory disease that is left untreated, this may result in infertility.

Bacterial vaginosis in men

Because BV affects the vagina, men can’t get bacterial vaginosis. However, research suggests that having unprotected sex with an uncircumcised partner may increase the risk of bacterial vaginosis.

The relationship between bacterial vaginosis and men is, once again, due to bacteria. Indeed, circumcised men have a different penile microbiome to men that are not circumcised.

That's because an uncircumsized penis still has foreskin which covers the head of the penis and creates a unique environment for bacteria to thrive.

Bacterial vaginosis in children

Bacterial vaginosis is most common in sexually active women of reproductive age, which means that it can affect teenage girls. It is possible to get BV without being sexually active because it can be caused by other factors.

For example, menstrual bleeding disrupts that natural pH of the vagina, making it more susceptible to microbiome imbalances. In addition, diet, smoking, perfumed soaps, bubble baths, and even stress are risk factors for bacterial vaginosis.

☝️If you are concerned about your child’s health, consult a doctor about the most age-appropriate testing for bacterial vaginosis.

Bacterial vaginosis testing

If you suspect that you have bacterial vaginosis, consult with your care provider. The doctor may ask you about your medical history, including previous vaginal or sexually transmitted infections, perform a pelvic exam, and collect a sample to check if it’s bacterial vaginosis or thrush, or something else.

You cannot diagnose bacterial vaginosis on your own. Testing is a critical part of the process to make sure that you have BV, and not a different problem. If you self-diagnose incorrectly, you may be tempted to treat it with unfounded home remedies for bacterial vaginosis or over-the-counter medication that may make things worse.

How to cure bacterial vaginosis

There are different bacterial vaginosis tablets, creams, and gels available over-the-counter and by prescription from your doctor. Always consult your care provider and get a diagnosis to make sure that you need medication and are getting the right one.

☝FACT☝ Asymptomatic bacterial vaginosis (that has no symptoms and causes no discomfort) does not need treatment.

Prescription BV treatment

Chronic, recurrent BV may require treatment with antibiotics. Always make sure to follow the instructions correctly because antibiotics have knock-on effects for the rest of your body, including your gut microbiome. Even if your symptoms go away sooner, always complete the course as prescribed by your doctor.

Bacterial vaginosis over-the-counter treatments

There are several bacterial vaginosis treatment over-the-counter options, such as Canesten bacterial vaginosis gel and home testing kits. To successfully treat BV at home, strict adherence to the instructions and specialist guidelines are required to avoid the risk of chronic bacterial vaginosis.

Bacterial vaginosis home remedies

Some sources might suggest you to use home remedies for bacterial vaginosis. These may include rinsing the outer sex organs with vinegar or boric acid, or applying essential oils. Do not use home remedies to treat bacterial vaginosis. They don’t work and can result in burns, damage to your genital organs, and infections.

Bacterial vaginosis treatment in pregnancy

Hormonal changes during pregnancy mean that 10–30% of women will get bacterial vaginosis. Untreated bacterial vaginosis during pregnancy increases the risk of complications, like low birth weight and premature birth. Consult your healthcare provider for bacterial vaginosis treatment in pregnancy.

☝️TIP☝️Always consult your doctor if you are pregnant and think you might have BV.

Probiotics for bacterial vaginosis

Oral probiotics ingested via the mouth can support female health. One study found that Lactobacillus fermentum LF15 and Lactobacillus plantarum LP01 positively affected the vaginal microbiome during BV by reducing the presence of pathogenic microorganisms.

Another clinical trial showed that daily oral probiotics containing L. fermentum (strain GR-1) and L. rhamnosus (strain RC-14) reduced the presence of potentially pathogenic bacteria and yeasts in the vagina.