Bacterial Vaginosis Test

When is a bacterial vaginosis test used?

Healthcare providers use this test to determine if you have bacterial vaginosis, a common bacterial infection.

A healthy vagina contains a lot of good bacteria and some bad bacteria. But sometimes, there’s an imbalance. When your vagina contains too many bad bacteria and not enough good bacteria, the imbalance leads to bacterial vaginosis.

Some common symptoms of BV are:

• Foul-smelling vaginal discharge (often described as fish-like).
• Gray or white vaginal discharge.
• Pain, irritation or itching.
• A burning sensation when peeing.

Who orders bacterial vaginosis tests?

A primary care provider (PCP) or gynecologist orders the test and collects a sample of your vaginal discharge in their office. Then a healthcare provider does one or more of the following:

• Looks at cells in the sample under a microscope.
• Runs tests on cells in the sample.
• Sends the sample to a laboratory for analysis.

How does a bacterial vaginosis test work?

The first step of this test is to get a sample of fluid from your vagina. There are several ways providers can test that sample for BV. The most common are:

• Wet mount: For a wet mount, a pathologist puts the sample of vaginal discharge on a glass slide mixed with a solution, then examines it under a microscope. Then, they examine the sample for bacteria, white blood cells or clue cells. These cells are found on your vaginal wall. If they have fuzzy borders, this indicates a bacterial infection. This test is also called a vaginal smear or wet prep.
• Whiff test: For a whiff test, your provider checks the sample of vaginal discharge for an odor. They add a special solution to the vaginal fluid sample. If the result is a strong fish-like smell, that can confirm bacterial vaginosis.
• Vaginal pH: A vaginal pH test measures the level of acidity versus alkalinity of the sample of vaginal discharge. Bacterial vaginosis makes pH higher than normal. This test alone can’t diagnose bacterial vaginosis, so it’s often used with another testing method.
• DNA test: Also called a PCR test, this method involves checking the genetic material in the fluid sample. This test is expensive and not used as often as the other methods.

Can BV be detected in urine?

No. A urine test detects bacterial infections in your urinary tract. But providers can’t diagnose bacterial vaginosis from a sample of your pee.

How do I prepare for a bacterial vaginosis test?

Your healthcare provider will tell you how to prepare for the test. You’ll likely have to avoid the following for 24 hours prior, as they can interfere with results:

• Douching.
• Having sex.
• Using tampons.
• Using vaginal medicines (for example, creams to reduce itching).

What can I expect on the day of the bacterial vaginosis test?

A BV test begins like a pelvic exam. You’ll remove your clothes from the waist down. You may have a blanket or paper sheet to drape over your legs. Then you lie down on an exam table and place your feet in stirrups to keep your legs up and apart.

The steps generally involve:

• Your healthcare provider inserting a medical tool called a speculum into your vagina. The tool may be covered in lubricant (a smooth, clear gel), so it inserts smoothly with little discomfort. The speculum gently spreads your vaginal walls apart so your healthcare provider can see inside your vagina. This part of the process may cause some discomfort or a feeling of pressure.
• Your healthcare provider inserting a long cotton swab or wooden stick into your vagina and gently scraping a bit of vaginal fluid.
• Finally, your provider putting the sample in a sterile container, then removing the speculum.
• You putting your clothes back on and going home right after the test.

What can I expect after a bacterial vaginosis test?

You may have some mild soreness or very light bleeding. But you’ll feel better quickly, and won’t have to restrict your activity after the test.