Medical Author: Melissa Stoppler, M.D.
Medical Editor: William C. Shiel, Jr., MD, FACP, FACR
Bacterial vaginosis is a mild infection of the vagina. This condition is caused by an imbalance in the growth of the bacteria that are normally populate the vagina. It is not known exactly why this imbalance in bacterial growth occurs.
This condition used to be called Gardnerella vaginitis, because Gardnerella is a type of bacteria that sometimes causes the infection. We now know that overgrowth of other types of bacteria can also cause bacterial vaginosis.
Unlike sexually transmitted infections, this infection results from bacteria that are normally found in the vagina. A woman does not get the infection from a sex partner. It is most common in sexually active women, but women who are not sexually active also can develop the condition.
About half of women with bacterial vaginosis have no symptoms. Others have variable amounts of vaginal discharge that usually has an unpleasant odor. The discharge is generally grayish-white but can be of any color or consistency.
Because vaginal discharge is also a symptom of other more dangerous infections such as gonorrhea and Chlamydia, you should see your doctor if you experience any abnormal vaginal discharge. A culture of the discharge can rule out other infections and establish the diagnosis of bacterial vaginosis.
While the infection itself is not considered dangerous, bacterial vaginosis should be treated with antibiotics. If not treated, the bacteria may spread up into the uterus or Fallopian tubes and lead to a more serious infection. Metronidazole (Flagyl) and clindamycin (Cleocin) are examples of antibiotics that are effective in treating bacterial vaginosis. Your doctor may prescribe antibiotics in pill form or as a cream or gel to be applied to the vagina.
After treatment, the condition generally resolves without complications, but up to 15% of women have recurrent symptoms that need to be treated with a second course of antibiotics.
Bacterial vaginosis can cause serious problems in pregnancy including premature labor, premature birth, infection of the amniotic fluid, and infection of the uterus after delivery. Screening for bacterial vaginosis and treatment if necessary during pregnancy can help prevent these complications.