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 – this is not known.
Bacterial vaginosis may occur at the same time as other infections or sexually transmissible infections (STIs).
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.
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. The link between specific sexual practices and BV is not conclusive; however, recent evidence supports the use of condoms to reduce the risk of this infection.
Diagnosis
During a medical examination, your doctor may notice:
- The 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 known as metronidazole is often used to treat the infection. 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 cream – 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 again 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
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.
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Bacterial vaginosis explained.
