Bacterial vaginosis (BV) can cause discomfort and pain of the vagina. It happens when natural bacteria levels are out of balance. Balanced levels of bacteria help keep the vagina healthy. But when too much of some bacteria grow, it can lead to BV.

Bacterial vaginosis can happen at any age. But it's most common during the reproductive years. The changes in hormones during this time make it easier for certain kinds of bacteria to grow. Also, bacterial vaginosis is more common among those who are sexually active. It's not clear why this is. But activities such as unprotected sex and douching raise your risk of having BV.


Symptoms of bacterial vaginosis include:

  • Thin, vaginal discharge that may be gray, white or green.
  • Foul-smelling, "fishy" vaginal odor.
  • Vaginal itching.
  • Burning during urination.

Many people with bacterial vaginosis have no symptoms.

When to see a doctor

Make an appointment to see a health care professional if:

  • Your vaginal discharge smells unusual and you have discomfort. Your doctor can help find the cause of your symptoms.
  • You've had vaginal infections before but your discharge seems different this time.
  • You have a new sex partner or different sex partners. Sometimes, the symptoms of a sexually transmitted infection (STI) are the same as those of bacterial vaginosis.
  • You thought you had a yeast infection but still have symptoms after self-treatment.

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Bacterial vaginosis happens when the vagina's natural bacteria levels are out of balance. The bacteria in the vagina are called the vaginal flora. Balanced vaginal flora help keep the vagina healthy. Usually "good" bacteria outnumber "bad" bacteria. The good bacteria are called lactobacilli; the bad bacteria are anaerobes. When there are too many anaerobes, they upset the balance of the flora, causing bacterial vaginosis.

Risk factors

Risk factors for bacterial vaginosis include:

  • Having different sex partners or a new sex partner. The link between having sex and bacterial vaginosis isn't clear. But BV happens more often when someone has different or new sex partners. Also, BV is more common when the sex of both partners is female.
  • Douching. The vagina is self-cleaning. So rinsing your vagina with water or something else isn't needed. It may even cause problems. Douching upsets the vagina's healthy balance of bacteria. It can lead to an overgrowth of anaerobic bacteria, causing bacterial vaginosis.
  • Natural lack of lactobacilli bacteria. If your vagina doesn't produce enough lactobacilli, you're more likely to develop bacterial vaginosis.


Bacterial vaginosis doesn't cause complications very often. But sometimes, having BV may lead to:

  • Sexually transmitted infections. If you have BV, you have a higher risk of getting an STI. STIs include HIV, herpes simplex virus, chlamydia or gonorrhea. If you have HIV, bacterial vaginosis raises the risk of passing the virus to your partner.
  • Infection risk after gynecological surgery. Having BV may increase the risk of developing an infection after surgery such as hysterectomy or dilation and curettage (D&C).
  • Pelvic inflammatory disease (PID). Bacterial vaginosis can sometimes cause PID. This infection of the uterus and the fallopian tubes raises the risk of infertility.
  • Pregnancy issues. Past studies have shown a possible link between BV and problems with pregnancy. These include preterm birth and low birth weight. New studies show that these risks may be due to other reasons. These reasons include having a history of early delivery. But the studies agree that you should be tested if you notice symptoms of BV while pregnant. If positive, your doctor can choose the best treatment for you.


To help prevent bacterial vaginosis:

  • Don't use scented products. Wash your genitals with warm water only. Scented soaps and other scented products may inflame vaginal tissues. Use unscented tampons or pads only.
  • Don't douche. Douching won't clear up a vaginal infection. It may even make it worse. Your vagina doesn't require cleansing other than normal bathing. Douching disrupts the vaginal flora, raising your risk of infection.
  • Practice safe sex. To lower your risk of STIs, use latex condoms or dental dams. Clean any sex toys. Limit your number of sex partners or don't have sex.

June 10, 2023
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