What is bacterial vaginosis?

Bacterial vaginosis (BV) is the most common cause of vaginal discharge that occurs in reproductive age women (women who have not gone through menopause yet). Up to a third of US women have bacterial vaginosis, and the number is somewhat higher amongst African-Americans, where up to one-half of women can have BV. Bacterial vaginosis does not usually cause serious health problems, but is treated more aggressively in pregnant women due to a possible link with preterm delivery.

What causes bacterial vaginosis?

Bacteria are a natural part of the vagina. For some reason, something upsets the normal balance of bacteria. Some of the bacteria can grow too rapidly and cause an imbalance. Also, not having enough of the right type of protective bacteria can contribute to the problem (the protective bacteria keep the BV bacteria from increasing in number).

What are the symptoms of bacterial vaginosis?

Between half to 75% of the women who have BV do not have any symptoms, and typically women who do not have symptoms do not need to be treated.

Common symptoms of BV include:

  • Off-white or grey discharge
  • Discharge that smells "fishy"
  • "Fishy" smell that is strongest after sex or during the menstrual cycle

Symptoms of an itchy or sore vagina are rarely due to bacterial vaginosis. Because BV has symptoms that are similar to other infections, it is important that you visit your health care provider if you think you have an infection in your vagina.

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