Bacterial Vaginosis

Bacterial vaginosis (BV) is the most common vaginal infection in women. Around 1 in 3 women will experience BV at some point in their lives. While most women have heard about thrush, few women have heard about bacterial vaginosis.

What is bacterial vaginosis?

Bacterial vaginosis occurs when there is a decrease in the healthy vaginal bacteria (lactobacilli) and an overgrowth of other bacteria. Some of these bacteria naturally live in your vagina but in lower numbers.

These other bacteria include Gardnerella vaginalisAtopobium vaginaeMobiluncus species, Prevotella species, and other BV-associated bacteria.  These bacterial changes lead to an increase in vaginal pH and amines which produce odour.

What causes bacterial vaginosis?

The exact cause of BV is unknown. We don’t know why some women get it and some don’t.

We do know that women who are sexually active are more likely to get BV than women who are not sexually active.

We also know that certain practices can increase your risk of bacterial vaginosis:

  • Sex with a new partner is associated with getting BV for the first time.
  • Sex with an ongoing partner after treatment and not using condoms, is associated with getting BV back again.
  • Having a female sexual partner.
  • Not using condoms all the time.
  • Cleaning inside the vagina with water, soap or other products (douching).


Read more about vaginal health

Is bacterial vaginosis sexually transmitted?

Research suggests bacterial vaginosis is likely to be sexually transmitted. This is not yet proven and we need to do more research to find out how it is being transmitted.

What are the symptoms of bacterial vaginosis?

BV symptoms include:

  • Milky, thin, white or greyish discharge.
  • Fishy or unpleasant odour (which can be worse after sex).

Rarely some women also experience:

  • Pain, itching or burning inside the vagina.
  • Itching around the outside of the vagina but this is more common with thrush.

These symptoms can be worse after sex or around your period.

Not all women experience all of these symptoms. Around half will not experience any symptoms at all.

How do I get tested for bacterial vaginosis?

If you think you may have BV, see your doctor.  Your doctor may examine you and  take a vaginal swab for testing.

Bacterial vaginosis is not routinely tested for as part your pap smear or STI screening.

How is bacterial vaginosis treated?

BV is treated with antibiotics (Metronidazole twice daily for 7 days) or vaginal cream (Clindamycin vaginal cream to be applied each night for 7 nights) prescribed by your doctor.

Treatment for bacterial vaginosis differs from treatment for thrush. Thrush treatments will not treat BV and BV treatments will not treat thrush.

Treatment for BV isn’t needed if you do not have symptoms, unless:

  • You are pregnant and have a history of pre-term delivery
  • You are having an invasive medical procedure such as the insertion of an IUD or termination of pregnancy.

How do I talk to my doctor about bacterial vaginosis?

Use this factsheet to help discuss your symptoms with your doctor.

You can also use this symptom checker. This may help diagnose your symptoms. It will also give you a referral letter to take to your doctor with the tests you might need.

Should my partner be treated for bacterial vaginosis?

Currently male partner treatment is not recommended as there’s insufficient evidence to show that it would be of benefit. However new research is underway to explore this further and new partner treatment trials are currently underway in Australia.

Your female sexual partners are far more likely to also have BV, so testing and treatment is recommended.

How do I take care of myself during treatment for bacterial vaginosis?

During treatment for BV it is best to:

  • Avoid alcohol (one of the antibiotics often given to women with BV, Metronidazole, interacts strongly with alcohol).
  • Avoid sexual contact or use condoms during treatment.
  • Make sure that you take the full course of antibiotics.

What happens if bacterial vaginosis isn’t treated?

BV is a very common condition and it will not cause most women any problems.  Some women find it goes away by itself without treatment.

However, it can lead to an increased risk of contracting sexually transmitted infections.  You can also be more likely to get pelvic inflammatory disease (PID).

If you are pregnant and experiencing symptoms of BV, it is important you see your doctor. BV can put you at a higher risk of miscarriage, pre-term (early) delivery or low birth weight babies.

How can I stop bacterial vaginosis coming back?

While the treatment for BV is usually very effective in the short term, women often get it back.  Around half of women will get BV again within 6-12 months of treatment.

We do not know why recurrence is so common after treatment.

Some women with recurring BV may benefit from a long term course of antibiotic gel used twice a week for 4 to 6 months.

There are some simple things you can do to lower your risk of infection.

Are there alternative treatments for bacterial vaginosis?

We know that many women do not like taking antibiotics and want to know if there is anything else they can do to stop BV coming back.

At the moment, there is no hard and fast scientific evidence that anything other than antibiotics will treat BV.

Some probiotic and lactic acid treatments for BV look promising, but further research is required. In the next few years it is likely non-antibiotic treatments will be available to help treat BV.

Other treatments are under evaluation.

There are also some simple things you can do to lower your risk of infection.

Sonia, age 30

“…even though I freshly showered as soon as I towelled myself off, and then obviously you go to put your undies on, like you get the smell and it was like ‘OK that’s not right’.”

If this sounds like you, you are not alone.  Talk to your doctor about your symptoms today.

Use our symptom checker: