Bacterial Vaginosis (BV): Symptoms, Causes and Treatment

Bacterial vaginosis (BV) is the most common cause of unusual vaginal discharge in women of reproductive age. It happens when the normal balance of bacteria in the vagina changes, and it often causes a thin, watery discharge with a “fishy” smell. BV is easy to diagnose and treat, but it often comes back, and recent Australian research has changed how doctors manage it, including treating some partners at the same time.

Here’s what BV is, what causes it, how it’s treated and how to reduce the chance of it coming back.

What is BV?

A healthy vagina contains lots of “good” bacteria (mainly lactobacilli) that keep it slightly acidic. In BV, these bacteria are reduced and other types of bacteria overgrow. BV isn’t caused by poor hygiene, and it’s nothing to be embarrassed about.

Symptoms

About half of people with BV have no symptoms. When symptoms occur, they can include:

• a thin, white or grey, watery vaginal discharge
• an unpleasant or “fishy” smell, which may be stronger after sex or during your period
• mild irritation around the vagina
• stinging when you wee (less common)

Itching, redness and thick white discharge are more typical of thrush, while burning and needing to wee often are more typical of a urinary tract infection (UTI). Our article Thrush, BV or UTI? How to tell the difference compares them side by side.

What causes BV?

The exact cause isn’t fully understood, but BV is closely linked with sex. According to healthdirect, things that make BV more likely include:

• a new sexual partner, or more than one partner
• sex without a condom
• having a female partner
• douching or washing inside the vagina
• using perfumed soaps, washes or sprays around the vagina
• having a copper IUD
• smoking

Is BV an STI?

BV hasn’t traditionally been classed as a sexually transmitted infection, but the Australian STI Management Guidelines now note that it behaves like one: it’s linked to sexual contact and can be passed between partners. People who have never had sex can still get BV, though.

Diagnosis

A doctor can often suspect BV from your symptoms. To confirm it, they may arrange a vaginal swab, which you can usually collect yourself at a pathology collection centre. Testing helps rule out thrush, trichomoniasis and other STIs, which can cause similar symptoms. If you’ve had a new partner, it’s a good time for a general STI check too.

Treatment

BV is treated with antibiotics, either as tablets or as a vaginal gel or cream. Your doctor will prescribe treatment if clinically appropriate. Finish the full course, even if your symptoms go away quickly, and avoid sex until treatment is finished and symptoms have gone.

Treating partners

BV comes back within a year for many people. A large Australian study led by Melbourne Sexual Health Centre found that treating male partners at the same time substantially lowered the chance of BV returning: about 35% of women had BV come back when both partners were treated, compared with about 63% when only the woman was treated (ASHM summary). As a result, the Australian STI Management Guidelines now recommend that regular male partners are treated at the same time, and that female partners are tested and treated if they have BV. Your doctor can talk through whether partner treatment is right for you.

BV in pregnancy

BV in pregnancy has been linked to a higher risk of premature birth and miscarriage. If you’re pregnant and have symptoms, see your doctor or midwife so you can be assessed and treated. Read more about our pregnancy consultations.

Reducing the chance of BV coming back

• Wash the vulva (outside) with water or a gentle soap substitute only. Don’t douche or wash inside the vagina.
• Avoid perfumed products, bubble baths and vaginal deodorants.
• Use condoms, especially with new partners.
• If you have a regular partner, ask your doctor about partner treatment.
• If you smoke or vape, quitting may help. Our quit smoking support can help you get started.
• Don’t share sex toys, or clean them well and use a new condom on them for each person.

Probiotics and yoghurt are sometimes suggested, but there isn’t good evidence that they prevent BV.

When to see a GP

• You have unusual discharge or a vaginal smell for the first time.
• Your symptoms haven’t gone after treatment, or BV keeps coming back.
• You’re pregnant and have any unusual discharge.
• You’ve had a new partner or think you may have an STI.

See a GP in person if you have pain during sex, pelvic pain or bleeding between periods, as you may need an examination.

When to get urgent help

Go to an emergency department or call 000 if you have:

• severe pain in your lower tummy or pelvis, especially with a fever
• heavy vaginal bleeding
• pregnancy with bleeding, fluid leaking, pain or cramping

How Teldoc can help

Our AHPRA-registered GPs can assess BV symptoms by phone or video, 7 days a week from 9 am to 7 pm (Sydney time), and most patients are seen within 15 minutes. Your doctor can arrange a swab, prescribe treatment if clinically appropriate with an eScript sent to your phone, and talk about partner treatment. BV consultations are bulk billed for eligible patients with a valid Medicare card. Learn more about our online BV treatment or see our fees page.

Frequently asked questions

Can BV go away on its own?

Sometimes, but it often doesn’t, and symptoms can be unpleasant. If you have symptoms, or you’re pregnant, see a doctor for assessment and treatment.

Can my partner give me BV?

BV is linked to sexual contact and can pass between partners. Australian guidelines now recommend treating regular male partners at the same time, and testing female partners, to lower the chance of BV coming back.

Is BV the same as thrush?

No. BV is caused by a change in vaginal bacteria and usually causes thin discharge with a fishy smell. Thrush is a yeast infection that usually causes itching and thick, white discharge. They need different treatments.

Why does my BV keep coming back?

BV often returns, especially if a regular partner hasn’t been treated. Talk to a doctor about partner treatment and other ways to reduce recurrence.

This article is general health information and isn’t a substitute for advice from your own doctor. If you’re worried about your health, speak to a GP. In an emergency, call 000.

Medically reviewed by Dr Vafa Derakshan (MBBS, FRACGP), September 2026