Bacterial vaginosis is caused by an overgrowth of certain bacteria in the vagina that are usually only found there in small numbers. This increases the risk of vaginal inflammation.
At a glance
- Bacterial vaginosis is one of the most common types of vaginal infections.
- It is estimated that BV affects about 5 percent of women.
- Vaginosis is caused by an overgrowth of certain bacteria in the vagina.
- At least half of all women who develop bacterial vaginosis do not have any noticeable symptoms.
- The infection increases the risk of vaginal inflammation.
- The risk of infection is higher in women who switch sexual partners frequently.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.
What is bacterial vaginosis?
Bacterial vaginosis (BV) is caused by an overgrowth of certain bacteria in the vagina that are rarely found there under normal circumstances.
This type of infection is usually harmless and often even goes unnoticed. However, bacterial vaginosis can cause a strong-smelling vaginal discharge and be very unpleasant for those affected. It also increases the risk of vaginal inflammation. Antibiotics can provide effective treatment for bacterial vaginosis.
What are the symptoms of bacterial vaginosis?
At least half of the women who develop bacterial vaginosis do not have any noticeable symptoms. When the condition is detected, it is usually by a very unpleasant, thin, grayish-white vaginal discharge that smells strongly of fish and is very unpleasant for a lot of women. This smell is often stronger after sex or during menstruation.
Symptoms like itching, a burning sensation and vaginal dryness are more likely to be signs of vaginitis (inflammation of the vagina). In such cases, the area around the vagina is often reddened and the mucous lining of the vagina is swollen. Vaginal inflammation may also result in problems when urinating (peeing) or during sex.
What causes bacterial vaginosis?
The vagina usually contains mostly lactic acid bacteria. Together with other bacteria they make up the vaginal flora and help to maintain a slightly acidic environment. The right acidity (pH level) can help to protect against germs.
Bacterial vaginosis can be caused by an imbalance in the acidic level of the vaginal environment: the number of lactic acid bacteria drops and other bacteria can reproduce quickly. Bacterial vaginosis is most commonly caused by bacteria called Gardnerella vaginalis.
What are the risk factors for bacterial vaginosis?
The risk of infection is higher in women who switch sexual partners frequently.
Excessive intimate hygiene or hormonal changes can also cause an imbalance in the vaginal flora and make bacterial vaginosis more likely.
How common is bacterial vaginosis?
Bacterial vaginosis is one of the most common types of vaginal infection. It is estimated that BV affects about 5 percent of women. The infection clears up on its own in about one third of women affected. Treatment is usually needed if it causes symptoms.
What are the potential consequences of bacterial vaginosis?
When the bacterial balance of the vaginal environment is disturbed, it’s easier for other disease-causing germs to become established there. BV can therefore lead to vaginal inflammation and sometimes to infections of the uterus and Fallopian tubes. It also increases the risk of contracting sexually transmitted infections (STIs).
In pregnant women, vaginal infections may slightly increase the risk of complications, such as premature labor, miscarriage, and premature birth.
How is bacterial vaginosis diagnosed?
It’s not always possible for gynecologists to tell bacterial vaginosis from other types of vaginal infections based only on the symptoms and so they take a sample of the vaginal secretion (smear) while examining the vagina. This sample can be used to measure the pH level to find out what types of bacteria it contains. Women with bacterial vaginosis usually have excessively high levels of gardnerella bacteria.
How is bacterial vaginosis treated?
Symptomatic bacterial vaginosis is usually treated with antibiotics to kill the germs. Suitable antibiotics are available in tablet form or as a suppository or cream for direct application in the vagina. It’s not necessary to treat the woman’s partner, as the treatment doesn’t prevent future infection.
Another treatment option is suppositories or capsules containing living lactic acid bacteria. These treatments are designed to protect the vaginal flora and restore the correct balance. There is not yet enough evidence on how well this method works.
Some women also try things like putting tampons that have been soaked in tea tree oil or natural yogurt in their vagina to treat the condition, but there has not yet been enough research about how effective or safe these kinds of home remedies are.
More detailed information on vaginosis and which treatments help can be found at gesundheitsinformation.de.
- Amaya-Guio J, Viveros-Carreno DA, Sierra-Barrios EM et al. Antibiotic treatment for the sexual partners of women with bacterial vaginosis. Cochrane Database Syst Rev. 2016 Oct 1;10(10):CD011701. doi:10.1002/14651858.CD011701.pub2.
- Centers for Disease Control and Prevention (CDC). Sexually Transmitted Infections Treatment Guidelines, 2021. (Morbidity and Mortality Weekly Reports: Recommendations and Reports). MMWR 2021; 70(4): 1-187.
- Deutsche Gesellschaft für Gynäkologie und Geburtshilfe (DGGG). Bakterielle Vaginose (BV) in Gynäkologie und Geburtshilfe. S2k-Leitlinie (in Überarbeitung). AWMF-Registernummer 015-028. 2021.
- Hainer BL, Gibson MV. Vaginitis. Am Fam Physician. 2011 Apr 1;83(7):807-15.
- Li C, Wang T, Li Y et al. Probiotics for the treatment of women with bacterial vaginosis: A systematic review and meta-analysis of randomized clinical trials. Eur J Pharmacol. 2019 Dec 1;864:172660. doi:10.1016/j.ejphar.2019.172660.
- Oduyebo OO, Anorlu RI, Ogunsola FT. The effects of antimicrobial therapy on bacterial vaginosis in non-pregnant women. Cochrane Database Syst Rev. 2009 Jul 8;(3):CD006055. doi: 10.1002/14651858.CD006055.pub2.
- Spence D, Melville C. Vaginal discharge. BMJ. 2007 Dec 1;335(7630):1147-51. doi:10.1136/bmj.39378.633287.80.
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