Overview

Bacterial vaginosis is a type of vaginal inflammation caused by the overgrowth of bacteria naturally found in the vagina, which upsets the natural balance.

Women in their reproductive years are most likely to get bacterial vaginosis, but it can affect women of any age. The cause isn't completely understood, but certain activities, such as unprotected sex or frequent douching, increase your risk.

Symptoms

Bacterial vaginosis signs and symptoms may include:

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

Many women with bacterial vaginosis have no signs or symptoms.

When to see a doctor

Make an appointment to see your doctor if:

  • You have vaginal discharge that's new and associated with an odor or fever. Your doctor can help determine the cause and identify signs and symptoms.
  • You've had vaginal infections before, but the color and consistency of your discharge seems different this time.
  • You have multiple sex partners or a recent new partner. Sometimes, the signs and symptoms of a sexually transmitted infection are similar to those of bacterial vaginosis.
  • You try self-treatment for a yeast infection with an over-the-counter treatment and your symptoms persist.

From Mayo Clinic to your inbox

Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. Click here for an email preview.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.

Causes

Bacterial vaginosis results from overgrowth of one of several bacteria naturally found in your vagina. Usually, "good" bacteria (lactobacilli) outnumber "bad" bacteria (anaerobes). But if there are too many anaerobic bacteria, they upset the natural balance of microorganisms in your vagina and cause bacterial vaginosis.

Risk factors

Risk factors for bacterial vaginosis include:

  • Having multiple sex partners or a new sex partner. Doctors don't fully understand the link between sexual activity and bacterial vaginosis, but the condition occurs more often in women who have multiple sex partners or a new sex partner. Bacterial vaginosis also occurs more frequently in women who have sex with women.
  • Douching. The practice of rinsing out your vagina with water or a cleansing agent (douching) upsets the natural balance of your vagina. This can lead to an overgrowth of anaerobic bacteria, and cause bacterial vaginosis. Since the vagina is self-cleaning, douching isn't necessary.
  • Natural lack of lactobacilli bacteria. If your natural vaginal environment doesn't produce enough of the good lactobacilli bacteria, you're more likely to develop bacterial vaginosis.

Complications

Bacterial vaginosis doesn't generally cause complications. Sometimes, having bacterial vaginosis may lead to:

  • Preterm birth. In pregnant women, bacterial vaginosis is linked to premature deliveries and low birth weight babies.
  • Sexually transmitted infections. Having bacterial vaginosis makes women more susceptible to sexually transmitted infections, such as HIV, herpes simplex virus, chlamydia or gonorrhea. If you have HIV, bacterial vaginosis increases the odds that you'll pass the virus on to your partner.
  • Infection risk after gynecologic surgery. Having bacterial vaginosis may increase the risk of developing a post-surgical infection after procedures such as hysterectomy or dilation and curettage (D&C).
  • Pelvic inflammatory disease (PID). Bacterial vaginosis can sometimes cause PID, an infection of the uterus and the fallopian tubes that can increase the risk of infertility.

Prevention

To help prevent bacterial vaginosis:

  • Minimize vaginal irritation. Use mild, nondeodorant soaps and unscented tampons or pads.
  • Don't douche. Your vagina doesn't require cleansing other than normal bathing. Frequent douching disrupts the vaginal balance and may increase your risk of vaginal infection. Douching won't clear up a vaginal infection.
  • Avoid a sexually transmitted infection. Use a male latex condom, limit your number of sex partners or abstain from intercourse to minimize your risk of a sexually transmitted infection.

July 21, 2021
  1. Bacterial vaginosis — CDC fact sheet. Centers for Disease Control and Prevention. https://www.cdc.gov/std/bv/STDFact-Bacterial-Vaginosis.htm. Accessed April 22, 2019.
  2. AskMayoExpert. Vulvovaginitis. Mayo Clinic; 2020.
  3. Pruthi S (expert opinion). Mayo Clinic, Rochester, Jan. 13, 2016.
  4. American College of Obstetricians and Gynecologists (ACOG) Committee on Practice Bulletins — Gynecology. ACOG Practice Bulletin No. 72. Vaginitis. Obstetrics and Gynecology. 2006;107:1195. Reaffirmed 2017.
  5. Frequently asked questions. Gynecologic problems FAQ028. Vaginitis. American College of Obstetricians and Gynecologists. https://www.acog.org/Patients/FAQs/Vaginitis. Accessed April 22, 2019.
  6. Sexually transmitted diseases treatment guidelines, 2015. Centers for Disease Control and Prevention. https://www.cdc.gov/std/tg2015/default.htm. Accessed April 22, 2019.
  7. Sobel JD. Bacterial vaginosis: Treatment. https://www.uptodate.com/contents/search. Accessed May 24, 2021.
  8. Bacterial vaginosis. Womenshealth.gov. https://www.womenshealth.gov/a-z-topics/bacterial-vaginosis. Accessed April 22, 2019.
  9. Flagyl (prescribing information). Pfizer; 2018. http://labeling.pfizer.com/ShowLabeling.aspx?id=570. Accessed April 22, 2019.
  10. Cleocin (prescribing information). Pfizer; 2018. http://labeling.pfizer.com/showlabeling.aspx?id=627. Accessed April 22, 2019.
  11. Tindamax (prescribing information). Mission Pharma; 2018. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=a0d01539-8413-4703-94cc-d221918630a1. Accessed April 22, 2019.
  12. Solosec (prescribing information). Lupin Pharmaceuticals, Inc.; 2021. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=551e43d5-f700-4d6e-8029-026f8a8932ff. Accessed May 24, 2021.