URL of this page: https://medlineplus.gov/lab-tests/bacterial-vaginosis-test/

Bacterial Vaginosis Test

What is a bacterial vaginosis (BV) test?

Bacterial vaginosis (BV) is an infection of the vagina. A healthy vagina contains a balance of both "good" (healthy) and "bad" (unhealthy) bacteria. Normally, the good type of bacteria keeps the bad type under control. A BV infection happens when the normal balance is upset and more bad bacteria grow than good bacteria.

Most BV infections are mild and sometimes go away on their own. Some women get BV and recover without even knowing they were infected. But BV infections can be more serious and may not clear up without treatment. Untreated BV may increase your risk of getting a sexually transmitted disease (STD), such as chlamydia, gonorrhea, or HIV.

If you are pregnant and have a BV infection, it can increase your risk of having a premature (early) delivery or having a baby with a lower than normal birth weight (less than 5 pounds, 8 ounces at birth). Low birth weight can cause serious health problems in a baby, including infections, breathing difficulties, and troubles with feeding and gaining weight.

A BV test can help you get diagnosed and treated so you can avoid these serious health problems.

Other names: vaginal pH test, KOH test, wet mount test

What is it used for?

This test is used to diagnose BV infections.

Why do I need a BV test?

You may need testing if you have symptoms of BV. These include:

  • A gray or white vaginal discharge
  • A strong, fish-like odor, which may be worse after sex
  • Pain and/or itching in the vagina
  • Burning sensation when urinating

What happens during a BV test?

A BV test is done in a similar way as a pelvic exam or Pap smear. During the test,

  • You will take off your clothes below your waist. You will get a gown or sheet as a cover.
  • You will lie on your back on an exam table, with your feet in stirrups.
  • Your health care provider will insert a special tool called a speculum into your vagina. The speculum gently spreads apart the sides of your vagina.
  • Your provider will use a cotton swab or wooden stick to collect a sample of your vaginal discharge.

The discharge will be looked at under a microscope to check for signs of infection.

Will I need to do anything to prepare for the test?

You should not use tampons, douche, or have sex for at least 24 hours before your test.

Are there any risks to the test?

You may feel some mild discomfort when the speculum is put in your vagina.

What do the results mean?

If your results show you have a BV infection, your health care provider will probably prescribe antibiotic pills and/or antibiotic creams or gels that you can put directly into your vagina.

Sometimes a BV infection will come back after successful treatment. If this happens, your provider may prescribe different medicine or a different dose of the medicine you took before.

If you are diagnosed with BV and are pregnant, it's important to treat the infection, because it can cause health problems for your unborn baby. Your health care provider will prescribe an antibiotic treatment that will be safe to take during pregnancy.

If your results show no BV bacteria, your health care provider may do more tests to find out the cause of your symptoms.

If you have questions about your results, talk to your health care provider.

Is there anything else I need to know about a BV test?

BV is not spread through female-to-male sexual contact. So if you are diagnosed with BV and have a male sexual partner, he will not need to be tested. But the infection can be spread between female sexual partners. If you have an infection and your partner is female, she should get a BV test.

Researchers aren't sure what causes BV, but there are steps you can take that may lower your risk of infection. These include:

  • Don't use douches
  • Limit your number of sex partners
  • Practice safe sex

References

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The medical information provided is for informational purposes only, and is not to be used as a substitute for professional medical advice, diagnosis or treatment. Please contact your health care provider with questions you may have regarding medical conditions or the interpretation of test results.

In the event of a medical emergency, call 911 immediately.