In the majority of cases, bacterial vaginosis (BV) will be diagnosed by a doctor based on the presence of symptoms.

Usually, it doesn’t require testing. But if you have symptoms or are sexually active with more than one person, a doctor may advise STI testing in order to rule out other possible causes of symptoms. This is especially important if the person with symptoms is pregnant, as STIs increase the risk of complications.

On this page we’ll cover:

When does someone need to be tested for BV?

If the signs of bacterial vaginosis are obvious enough, then testing isn’t always necessary. However, someone experiencing symptoms should see a doctor or nurse for further advice; because the symptoms of BV can be quite similar to those associated with STIs.

As a result, testing may be done in the presence of bacterial symptoms to rule out other possible infections; particularly if the person with symptoms is sexually active. Bacterial vaginosis also increases the transmission risk of other STIs, and this is another reason why a doctor may want to undertake a test.

When someone presents BV symptoms during pregnancy, a doctor may once again choose to confirm a diagnosis with a test, to lower the risk of other STIs (which can cause pregnancy complications) being undetected.

Where can I get tested for BV?

You can get tested for BV at a sexual health (GUM) clinic. Your GP can also perform an examination and diagnose BV where appropriate, or recommend further testing if needed.

Some community hospitals also have sexual health departments which can carry out an examination and testing. In some cases you can contact these services directly, but in others you may need to be referred through your GP.

Self-testing kits are available buy online for BV. Some of the work by testing the pH levels in the vagina; whereas others work by testing for the presence of the bacteria responsible.

For example, a test kit is available at which screens for gardnerella vaginalis, which can often be responsible for causing BV.  

How does a doctor diagnose bacterial vaginosis?

The symptoms of bacterial vaginosis are quite distinct. A doctor or nurse will normally ask the patient to answer a few questions about these, and they may also ask about their sexual activity. If these symptoms strongly indicate BV, this will normally be sufficient for a diagnosis.

In some cases, the doctor or nurse may examine the vagina if they aren’t sure from the patient’s description that what they have is BV. If they think that an STI might be the cause, then they may need to take a swab of the vagina or ask for a urine sample, to send off for testing. This tests for different types of bacteria that might be causing the infection.

A doctor can also perform a pH test to help them diagnose BV. The discharge that is caused by BV tends to have a higher pH level than normal. pH is measured from 0 (very acidic) to 14 (very alkaline). A healthy vagina would have a pH of between 3.8-4.5. So, a doctor may use pH paper on a sample of discharge to see if it is over 4.5, which would indicate conditions in which the bacteria are able to grow.

What happens if I am diagnosed with BV?

Not everyone who has bacterial vaginosis will need treatment. In some instances, the body can restore the natural balance of bacteria in the vagina on its own, and symptoms can resolve themselves.

In cases where symptoms are problematic or persistent, a doctor can prescribe antibiotic tablets or topical antibiotic treatment, to help tackle the bacteria responsible.

You can read more on our page on treating bacterial vaginosis.

Page last reviewed:  26/10/2018