Bacterial vaginosis explained

Bacterial vaginosis (BV) is caused by an imbalance of the bacteria normally present in the vagina. In women with BV, the normal healthy bacteria (in particular, lactobacilli) are replaced by an overgrowth of other, mixed bacteria.

Bacterial vaginosis has, in the past, been called nonspecific vaginitis or gardnerella vaginitis. This is misleading as it implies that the bacterium Gardnerella vaginalis is the cause of BV. BV is now thought to be a polymicrobial (caused by many different organisms) condition, the exact cause of which is unknown.

Symptoms

Symptoms of BV may include:

• A watery, white or grey discharge instead of normal vaginal secretions
• A strong or unusual odour from the vagina, often described as a ‘fishy’ odour.

About half of all women with bacterial vaginosis will have no symptoms. Bacterial vaginosis may occur at the same time as other infections or sexually transmissible infections.

How bacterial vaginosis is spread

Although it is not clear how bacterial vaginosis is transmitted, it is more common in women who are sexually active. It sometimes develops soon after intercourse with a new partner. Women who have female sexual partners may be at higher risk than women who have sex with male partners.

Research has not conclusively found a link between BV and specific sexual practices or acts – however, recent evidence supports the use of condoms to reduce the risk of this infection.

Diagnosis

During a medical examination, your doctor may notice:

• A discharge or odour
• Decreased acidity of the vaginal fluid – this can occur even if you have not noticed any symptoms.

Treatment

If you have no symptoms, treatment is usually not required. You should receive treatment if you:

• Have symptoms or your doctor has noticed signs of bacterial vaginosis
• Are about to have a medical procedure that could allow bacteria into the uterus – for example, insertion of an IUD or termination of pregnancy
• Are pregnant – your obstetrician may need to be consulted about treatment.

Antibiotics are used to treat the infection

An antibiotic called metronidazole can be used to treat the infection when indicated. If your doctor prescribes metronidazole you will need to:

• Take the antibiotic twice a day for seven days
• Take the tablets after meals – this can reduce the nausea and upset stomach that is sometimes associated with metronidazole
• Avoid drinking alcohol during treatment.

Your doctor can prescribe a vaginal cream if you are unable to take metronidazole, such as clindamycin – this is applied to the vagina for seven nights.

Recurrences can occur

Even after treatment, about half of the women with bacterial vaginosis will get the condition back within six to 12 months. This may be due to the treatment not working or to re-infection. Treating the male partner of an infected woman does not seem to reduce the risk of recurrence. Female partners of infected women are at increased risk, so screening for BV and treatment (if required) is recommended.

Prevention

Most cases of bacterial vaginosis appear to be associated with sexual activity. Condoms have been shown to protect against infection and safe sexual practices are recommended for all women regardless of the gender of their partners.

Where to get help

• Your doctor
• Melbourne Sexual Health Centre Tel. (03) 9341 6200 or 1800 032 017 or TTY (for the hearing impaired) (03) 9347 8619

Things to remember

• Bacterial vaginosis can cause a watery, white or grey vaginal discharge and odour.
• It may develop soon after sex with a new partner.
• An antibiotic known as metronidazole is used to treat the infection.

You might also be interested in:

• Infections - bacterial and viral.
  
• Sexually transmissible infections - overview.
  
• Sexually transmissible infections - signs and symptoms.
  

Want to know more?

Go to More information for support groups, related links and references.

This page has been produced in consultation with and approved by:

(Logo links to further information)

Melbourne Sexual Health Centre

Fact sheet currently being reviewed.
Last reviewed: April 2011

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<a href="http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Bacterial_vaginosis_explained?open">Bacterial vaginosis explained - Better Health Channel</a><br/>
Bacterial vaginosis (BV) is caused by an imbalance of the normal bacteria in the vagina. Symptoms may include a watery, white or grey discharge and vaginal odour. Bacterial vaginosis has mistakenly been called nonspecific vaginitis or gardnerella vaginitis. It is most commonly associated with sexual activity. Antibiotics can treat the infection.

Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your qualified health professional. Content has been prepared for Victorian residence and wider Australian audiences, and was accurate at the time of publication. Readers should note that over time currency and completeness of the information may change. All users are urged to always seek advice from a qualified health care professional for diagnosis and answers to their medical questions.

For the latest updates and more information, visit www.betterhealth.vic.gov.au

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