BV (the abbreviation is widely used among clinicians) is called “Vaginosis” instead of “Vaginitis” because germs do not actually invade tissue to cause inflammation. The condition simply involves overgrowth of a variety of bacteria, which replace the healthy germs normally present in the vagina. The most common of these bacteria is Gardnerella vaginalis, but many others also contribute (the condition used to be called “Gardnerella,” but the name was changed to reflect the variety of germs).
Symptoms are mainly an excessive vaginal discharge, which may smell bad, but doesn’t itch or burn. However, the various combinations of germs responsible for BV are often found in women without any symptoms at all. It does not seem useful to go looking for BV among women without symptoms, not even if they’re pregnant, because treating them doesn’t change anything.
Women who have never had sex do not get BV. However, it is not truly an STD, because once the unhealthy germs are present, the condition can come and go without having sex. It’s also debatable whether men have any counterpart to BV, which would speak against consistent sexual transmission. In contrast to STDs, BV commonly occurs in women who only have sex with women. It is not recommended to treat partners of women with BV (either male or female), although some clinicians elect to do so.
To diagnose BV, we seek 3 of the following 4 criteria for diagnosis:
- Significant discharge that’s somewhat darkish (not clear or pure white)
- pH ≥5
- Positive Whiff Test — fishy odor noted when drop of KOH is added to discharge
- Clue Cells seen by microscope — normal vaginal epithelial cells with their edges completely covered by tiny bacteria (>20% of cells should look like this)
Of note, the “Whiff Test” above is especially significant in that if it’s negative, the discharge is highly unlikely to be BV. See our topic Vaginal Discharge for more about diagnosis.