Bacterial vaginosis (BV) is the overgrowth of specific types of bacteria in your vagina that result in bad smells and unusual discharge. True BV produces a fishy odour and discharge, but because it does not technically cause inflammation, there will be no itching, soreness or redness.

‘Typical’ BV is caused by a bacteria called Gardnerella vaginalis, but usually this bacteria has ‘friends’ that it uses to help build its home and defences, which may contribute to other symptoms you may be experiencing. These ‘friends’ don’t cause BV on their own, but are known as BV-related bacteria. There are a few major suspects here that are heavily linked with G. vaginalis.

True BV is quiet, but can be pungent. If you have itching, swelling, soreness or other symptoms, it means you have more than just BV (G. vaginalis) or not have BV at all. There are many crossover bacteria that can co-exist together to create a unique set of symptoms. It’s this set of symptoms that will tell you what’s lurking, and therefore what to get tested for or what treatments to choose. We review this in Killing BV and the support section.

For example, the odour may be more like rotten meat or a bit off than fishy, which matters – it may mean you have aerobic vaginitis. Other symptoms can include an ammonia or vinegar odour, green or yellow discharge, itching (which be worse at night), and a lack of response to typical treatments.

     Symptoms of BV by itself

     Symptoms of BV+, AV or other vaginal microbial imbalances or infections

  • Itching
  • Redness
  • Soreness
  • Pain after sex
  • Cramping
  • White, yellow, green, clumpy, thick or bloody discharge
  • Odour is rotten or off (not fishy) or like ammonia or vinegar
  • A test may come back with no results (testing for the wrong thing)
  • Pain
  • Rawness
  • Itching
  • White, thick, green or yellow discharge

     Diagnosis of BV

Usually you will get a swab to see whether you have large numbers of G. vaginalis and how many lactobacilli you have. A vagina that is low in lactobacilli and high in G. vaginalis is a vagina considered to have BV, generally speaking. But, there are variations on this, so read on to make sure you are well-informed before going to the doctor. The wrong test can lead to misery!

The type of bacteria you have in your vagina matter when it comes to figuring out what sort of vaginal bacterial imbalance you have, but medical testing is usually inadequate and diagnoses BV when there may be more going on. Ask for proper PCR testing when you visit your doctor if you have any of the BV+ or AV symptoms, as the treatment required is different. Some AV or BV+ bacteria are antibiotic resistant.

Usually BV – whether it is truly BV or not – is treated using standard antibiotics that may or may not work, either temporarily or over the longer term. This lays the groundwork for recurrent vaginal problems that are resistant to many types of treatment.

     Treatment for BV

The doctor will usually prescribe metronidazole, an antibiotic. You can, however, get rid of BV many ways, and the less antibiotics we use, the better. We have outlined a range of effective treatments for recurrent BV, AV, urinary tract infections and yeast infections in Killing BV, our definitive guide on cleaning up the mess left by BV (or any other non-STI vaginal infection).

First thing to ensure is proper testing, then making a treatment decision based on your results.

     How BV works in your vagina

An overgrowth of bad bacteria causes your vaginal environment to become hostile to your healthy bacteria, lactobacilli. The bad bacteria use various weapons to take over your vagina: they create a more alkaline environment, stop your cells from being able to defend themselves, and many of them create a sticky antibiotic-resistant biofilm to keep safe from treatments, including antibiotics. This is why BV can be unresponsive to antibiotics and keep on reappearing, no matter what you do.

     What is a bacterial biofilm?

A biofilm is like a film of wax over your vaginal cells that provides a safe haven for many types of bacteria, which is why BV is known as a polymicrobial – many microbe – condition. The main culprit in BV is understood to be Gardnerella vaginalis, but this microbe is far from the only major player. Many microbes create biofilms, including lactobacilli, which are your good bacteria.

The biofilm is what keeps BV ‘returning’ time and again because it never really goes away. Antibiotics, probiotics and home remedies do not get rid of the biofilm, which is why BV can seem impossible to get rid of. BV is curable, but you need to use different tools, which we explain in detail in our book on removing the biofilm and curing your BV for good, Killing BV.

     Typical treatments for BV and why they don’t work on recurrent BV

BV can recur over a lifetime despite multiple treatments, typically metronidazole, a common antibiotic that only works about half the time. Your doctor likely doesn’t understand the nature of vaginal biofilms, and even if they did, doesn’t know the options for clearing you BV up for good using biofilm busters, antimicrobials and recolonisation.

This is why your doctor keeps prescribing you antibiotics over and over, may refuse proper or further testing (PCR testing), and doesn’t have much for you if the first or second round doesn’t work.

You may have tried apple cider vinegar, hydrogen peroxide, lactic acid, vitamin C, vitamin D, vitamin B, folic acid, probiotics and yoghurt. In Killing BV, we explain why these treatments have continually failed, and provide you with a dedicated treatment plan to get rid of your BV once and for all.

     How do you know if you have BV?

The emerging wisdom is that BV is an umbrella term that is being used to describe bad smells and discharge, but what we know about BV is evolving. The term has now become a bit foggy, and is being used somewhat incorrectly by many practitioners.

  • Bacterial vaginosis = Gardnerella vaginalis and friends
  • Aerobic vaginosis = E. coli, E. faecalis, E. faecium and friends
  • Both conditions leave your vagina without much or any lactobacilli

BV symptoms caused by G. vaginalis are pretty specific – the fishy vaginal odour is your first clue (but this can be caused by some sexually transmitted infections – trich or gonorrhoea), plus the discharge.

But, you may have watery discharge, no discharge, no smell, and no other extra symptoms (asymptomatic). You could have been diagnosed with BV via a swab taken at your doctor’s office. The test will come back high for G. vaginalis and you will have a higher than normal pH.

     The precise cause of your symptoms – fishy odour, discharge

The odour is caused by a chemical reaction of molecules in your vagina that results in the production of trimethylamine (TMA), which is the exact same molecule that causes fish to smell like fish. You can read more about the exact reaction here.

The watery discharge is caused by enzymes that the bacteria excrete breaking down your naturally-produced vaginal mucous. This causes it to become watery. It is also why BV can trigger preterm birth – the mucous plug that holds the fluid in the womb gets broken down by the enzymes.

Any itch is due to irritation and damage to your vaginal cells caused by the bacteria and biofilm.

     Who gets BV?

BV is one of the most common vaginal infections in the world, and affects all populations almost equally, though women of African descent naturally have fewer protective lactobacilli in their vaginas and are more prone to BV than other groups of women. (Read more about black women and BV here.)

Children do not get BV, but past puberty, any woman can get BV whether they are sexually active or not – while BV can be sexually transmitted, it isn’t always. The bacteria may naturally reside in the vagina, but when the balance of good bacteria is off for whatever reason, the bad bacteria can overgrow from something as slight as a pH change (think semen, menstrual blood), causing an imbalance. It is not an infection per se, but an imbalance of bacteria (dysbiosis) that results in symptoms like fishy odour, itch and watery discharge.

     The biofilm causes recurrent BV

Recurrent BV is caused by the sticky bacterial biofilm of Gardnerella vaginalis, which blocks your friendly microbes from controlling the lion’s share of your vaginal surface area. The planktonic bacteria may be killed off by antibiotics, but the biofilm remains.

Women often think that their BV is ‘coming back’ all the time, especially after sex where semen enters the vagina or a menstrual period. This happens because both semen and menstrual blood have an alkaline pH. Learn more about BV and pH here. 

The symptoms you are experiencing are caused by your vaginal environment becoming an unfriendly home to your good microbes.

Read Killing BV and treat your biofilms and cure BV

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