Bacterial Vaginosis: Symptoms...

When you go to your healthcare provider with questions about vaginal discharge, he or she will have several diagnoses in mind to account for it. These may include:

• The discharge is normal for you
• Candidiasis (thrush, or a yeast infection)
• Trichomonas vaginalis (trichomoniasis)
• Bacterial vaginosis
• To find out which of these is the case, a few simple tests are done. The provider will carry out a speculum examination and take some swabs from high in the vagina. These swabs will be tested for:
• A characteristic smell—this is called the whiff test. A small amount of an alkali is added to a microscope slide that has been swabbed with the discharge—a 'fishy' odour is a positive result for bacterial vaginosis.
• Loss of acidity—the vagina is normally slightly acidic (with a pH of 3.8–4.2), which helps to control bacteria. A swab of the discharge is put onto litmus paper to check the acidity. A positive result for bacterial vaginosis would be a pH of over 4.5.
• 'Clue cells'—so called because they give a clue to the reason behind the discharge. These are epithelial cells (like skin) that are coated with bacteria. They can be seen under microscopic examination of your discharge.

Two positive results in addition to the discharge itself are enough to diagnose BV. If there is no discharge, then all 3 criteria are needed.