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This is an imbalance of the normal bacteria in the vagina. This article provides details of the condition and what treatment is available.

bacterial vaginosis


  • Bacterial vaginosis is an imbalance of the normal organisms in the vagina
  • It is not an STD but can be caused by increased sexual activity
  • The condition is common and causes a discharge with a fish-like odour
  • The problem may be more obvious after sex or during menstruation
  • Bacterial vaginosis is easily treated with antibiotics 

What is it?

Bacterial vaginosis (BV) was formally called Gardnerella. The balance of normal bacteria (lactobacilli is changed in favour of other bacteria (e.g. gardnerella and some other species such as bacteroides and mobiluncus).

It is not a STD but is linked to increased sexual activity. A change in sexual partners and douching may increase the risk of developing the problem.

The condition produces an unpleasant vaginal discharge because of an overgrowth of these other bacteria in the vagina, including an organism known as Gardnerella vaginalis.

It is a common problem. It is thought to cause up to 50 percent of cases of vaginal discharge. It has also been reported in 15 to 29 percent of pregnant women.

Factors like stress, a presence of another STD, and the use of perfumed feminine hygiene products may also increase the risks.

 BV may disappear without treatment, but it has been linked to serious conditions such as pelvic inflammatory disease, premature labour, recurring urinary tract infections, infections after labour, uterine infections after abortion or the insertion of an IUD and surgery (e.g. prior to hysterectomy). Treatment is recommended in these higher risk situations.

What are the symptoms?

An unusual vaginal discharge is the main symptom of the condition.

 A fish-like odour is noticed. It may be more obvious after sexual intercourse or during menstruation. The discharge may be white or have a gray tinge.

However, about half the women who have it do not notice any symptoms and only discover they have it during a physical examination followed by laboratory tests.

Ninety percent of women seeking treatment complain of discharge, 70 percent mention odor and 45 percent have irritation.

What is the treatment?

It is not necessary to treat the condition if it is causing no symptoms, except in the high risk situations outlined above.

The condition is easily cured with the use of antibiotics which can be taken in tablet form or by a cream applied to the vagina. Treatment is effective in about 90 percent of cases (e.g. ornidazole for 5 days). One off single ("stat") doses are safe and effective as well.

Metronidazole (400 mg twice a day for 7 days ) is effective and seems to has the safest and well documented record in pregnancy and lactation .

Some treatments should not be taken in the first part of pregnancy - check with your doctor.

Different antibiotics or suppositories can be used for recurrent infections.

Sufferers should also be screened for sexually transmitted diseases.

Male sexual partners do not routinely need treatment and women without symptoms may decline treatment.

Pregnant women should be treated because of the increased risks of premature labour.

How can it be prevented?

Avoid douching and feminine hygiene sprays. The use of condoms for a few months may also be helpful in preventing the alkalinity of semen affecting the vagina (i.e. reducing the natural protective acidity).

Future Trends.

Researchers are studying the organisms involved in BV and trying to understand how sexual activity may cause it.

Scientists are also investigating how the condition can lead to pelvic inflammatory disease and problems in pregnancy.

Getting help

Your doctor, sexual health service or family planning clinic will be able to help.

It is important to have proper confirmatory swabs done and get follow up advice if problems persist.

See also:

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