Bacterial vaginosis (BV) is a common yet poorly understood condition in which the balance of bacteria inside the vagina becomes disrupted.
Around one in three women will experience at least once episode of BV at some point.
This imbalance often triggers a change to the usual vaginal discharge, which results in a fishy smelling, greyish discharge from the vagina. However, half of women with bacterial vaginosis have no symptoms.
See your GP if you notice any abnormal discharge from your vagina, especially if you are pregnant. It is important to get this type of symptom diagnosed quickly to rule out other infections and prevent complications (see below).
If you do not have symptoms, there is no need to get tested as bacterial vaginosis without symptoms does not pose a threat to health or to pregnancy.
Read more about the symptoms of bacterial vaginosis.
What causes bacterial vaginosis?
The vagina contains a mix of so-called "good" bacteria, which can help protect against infection, and a smaller amount of "bad" bacteria, which can cause infection.
In cases of BV, the bad bacteria begin to outnumber the good bacteria, leading to inflammation inside the vagina, which can result in the fishy discharge.
What leads to this imbalance is still unclear. It is not classed as a typical sexually transmitted infection (STI), but it can develop after having sex with a new partner.
There is no evidence that a woman with BV can pass on any type of infection to her male sexual partner. But the same may not be true for women who have sex with other women.
You can also get bacterial vaginosis if you:
- use scented soaps or bubble baths
- have an intrauterine device (IUD)
- smoke
- use vaginal deodorant
Read more about the possible causes of bacterial vaginosis.
Treating bacterial vaginosis
BV can usually be successfully treated using a course of antibiotic tablets or gel.
However, it is common for BV to reoccur. Over half of women successfully treated with BV will have a reoccurrence of symptoms, usually within six months.
Women who have very frequent episodes of BV may be referred to a gynaecologist.
Read more about treating bacterial vaginosis.
Complications
BV is a concern if it develops in pregnant women as it increases the risk of pregnancy-related complications, such as premature birth or miscarriage. However, the increase in risk is small.
As a precaution, you should contact your GP if you are pregnant and you begin to have vaginal discharge (although discharges can be a normal part of pregnancy).
Bacterial vaginosis can also increase your risk or getting some STIs.
Read more about the complications of bacterial vaginosis.
