Tests for Bacterial Vaginosis

Tests for Reference bacterial vaginosis Opens New Window take samples of fluid and cells from the Reference vagina Opens New Window to see if this vaginal infection is present. Bacterial vaginosis has also been called nonspecific vaginitis, Haemophilus vaginitis, or Gardnerella vaginitis.

Bacterial vaginosis is caused by a change in the balance of microorganisms found in a healthy vagina. A healthy vagina normally has many microorganisms in it. The microorganisms involved in bacterial vaginosis include Gardnerella, Mobiluncus, Bacteroides, and Mycoplasma. When bacterial vaginosis is present, these microorganisms increase in number while the number of healthy microorganisms decrease.

Many women with bacterial vaginosis do not have symptoms. The most common symptom of bacterial vaginosis is an increase in a grayish white vaginal discharge, unlike normal vaginal discharge. The discharge often has a fishy smell.

Women who have bacterial vaginosis during pregnancy have a higher chance of miscarriage, early (preterm) delivery, and an infection after delivery, so it is important for pregnant women who have symptoms to be tested for bacterial vaginosis.

Several tests can be used to find bacterial vaginosis:

• Wet mount. A sample of vaginal discharge is mixed with a salt solution on a microscope slide. The slide is checked for bacteria, Reference white blood cells Opens New Window, and unusual cells called clue cells. If clue cells are present, it means bacterial vaginosis is present.
• Whiff test. Several drops of a potassium hydroxide (KOH) solution are added to a sample of vaginal discharge to see whether a strong fishy odor is produced. A fishy odor on the whiff test usually means bacterial vaginosis is present.
• Vaginal pH. The normal vaginal Reference pH Opens New Window is 3.8 to 4.5. Bacterial vaginosis often causes the vaginal pH to be greater than 4.5.
• Oligonucleotide probes. This test finds the genetic material (Reference DNA Opens New Window) of this bacteria. An oligonucleotide probe test is very accurate but is not available in all labs.

Bacterial vaginosis may be found during a Reference Pap test Opens New Window. But a Pap test is not recommended as a test to find bacterial vaginosis.

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