What Is Bacterial Vaginosis?


Bacterial vaginosis (BV) is a vaginal infection. It is a result of an overgrowth of the vaginal flora - the different kinds of healthy vaginal bacteria. The actual cause of BV is unknown, however, anything that changes the natural chemistry and pH of the vagina can disprupt the levels of bacteria and cause this infection. 

The Lactobacilli are the predominant microbiota in the female vagina and BV can occur as a result of the reduction in the number or variety of Lactobacillus species. The loss of hydrogen peroxide-producing Lactobacilli can lead to the overgrowth of anaerobes (Bacteria that thrive in the absence of oxygen). Of these anaerobes, Gardnerella vaginalis is chief. G. vaginalis creates an environment that enables other opportunistic bacteria to grow. It also promotes accesses for pathogenic microbes(STDs) to the upper genital tract.G. vaginalis  also produces enzymes that fight against the body's defense system to these sexually transmitted diseases. BV is not a sexually transmitted disease (STD) but it can increase the chances of getting one, and STDs likewise, can enhance the risk of developing bacterial vaginosis. The role of sexual intercourse in developing BV is linked to the fact that transmission of bacteria during sexual intercourse could alter the normal flora of the vagina. BV can also increase the risk of premature delivery in pregnancy.

Reproductive people with vaginas, aged between 15 - 49 years are more likely to experience bacterial vaginosis but the overgrowth of bacteriacan affect all ages.  BV rarely presents in people who have never had sex. Some studies have also shown that it is more common in those who begin sexual activity very early or who have multiple sexual partners,commercial sex workers, and people who share intimate toys or underwear.

Cause of bacterial vaginosis

The exact cause of bacterial vaginosis is unknown, however, some factors known to offset the natural balance of vaginal flora can increase the risk of developing BV.

These risk factors include:

  • Washing and Douching

The habit of rinsing  the vagina with a strong cleansing agent (over-the-counter vaginal products, soap bars, liquid soap and body washes, etc.) can affect the pH of the vagina pH and lead to bacterial vaginosis.

  • Multiple sexual partners or a new sex partner

The link between this isn't fully understood. But studies have shown that women who have multiple sex partners or who get involved with a new partner frequently come down with BV.

  • High frequency of sexual intercourse

While the number of times being referred to as "high" may vary amongst people, a hyperactive sexual drivehas been associated with BV. Commercial sex workers most likely fall under this category as they are at high risk of having bacterial vaginosis.

  • Recent antibiotic use

Use of  antibiotics especially for prolonged periods could alter the vaginal chemistry and cause BV

In some, a contraceptive device like IUD could predispose them to having bacterial vaginosis.

  • Bubble bath

Hot, scented or bubble baths  can disrupt the normal vaginal flora and cause BV.

  • Cigarette smoking

Smoking can promote theovergrowth of vaginal bacterial flora.

  • Menstruation

As the monthly reproductive cycle can alter the pH and balance of healthy bacteria in the vagina, it can often trigger bouts of  bacterial vaginosis, especially if there has been previous episodes of BV.

NB: It should however be noted that bacterial vaginosis cannot be contracted from toilet seats, swimming pools or bedding.

Signs and symptoms of bacterial vaginosis

BV can be asymptomatic (without symptoms), however common symptoms include:

  • Vaginal odor (the most common symptom and usually the initial sign. It is often recognized after sexual intercourse. Described as a foul-smelling/fishy vaginal odor)
  • Vaginal discharge (Thin grey, whitish or greenish vaginal discharge which can be watery)
  • Vaginal itching
  • Painful or burning sensation during urination
  • Painful sexual intercourse

Managment and treatment for bacterial vaginosis

Prior to managing bacterial vaginosis, a diagnosis has to be made. Primary diagnosis is based first on the signs and symptoms like vaginal discharge, odour, itching and painful urination.

A sample of vaginal discharge may be taken to make a clinical diagnosis..

Treatment of symptomatic bacterial vaginosis  usually involves the use of antibiotics, of which Metronidazole and Clindamycin can be used in different combinations. The dosage and duration of use is dependent on the instruction of your health care provider. Even if your symptoms subside early, make sure to complete your medications as directed to prevent recurrent infection. Also, abstaining from sexual intercourse during the period of treatment is advised. 

If you are pregnant contact your local GP or midwife as BV should be treated to prevent complications from the infection. BV can reccur after treatment but your health care provider will guide you on the next step of management as well as try to identify possible triggers. 

Further complications

In cases of untreated BV or poorly treated infection, the following complications could result:

  • Pelvic inflammatory disease

When the disease spreads to involve upper genital organs like the ovaries, uterus and fallopian tubes. This can lead to issues with child bearing.

  • Premature delivery/ low birth weight in pregnant women

In pregnancy, BV has been associated with early delivery of babies which can lead to infant health conditions. 

  • Neonatal infections

Babies of pregnant mothers with BV could get infected on their skin, brain and eyes on delivery.

  • Sexually transmitted diseases

Bacterial vaginosis makes you more susceptible to contracting STDs.

  • Post-surgical infection

Bacterial vaginosis can lead to infections and delay in recovery after surgeries including removal of the uterus (hysterectomy).

The overall outcome of bacterial vaginosis is excellent if treated properly and on time. For this reason, you should see your doctor once you have any of the symptoms already discussed. In order to prevent a recurrence, you  should avoid vaginal deodorants and simply wash your vagina with clean water only. Showers are preferrable to baths as you do not immerse the vagina in water - this can affect the physical chemistry of the vagina.. Do not smoke as smoking is a risk factor to having BV.


How common is bacterial vaginosis?

Bacterial vaginosis is very common, especially among people assigned female at birth who are of reproductive age (between 15 to 49). 

Who is at risk of bacterial vaginosis?

People who have cis- (original) or neo- (new) vaginas  who have multiple sexual partners or new sexual partners are at risk of developing BV. Vaginal douching and the use of vaginal deodorants, soaps and body washes on the vagina are risk factors too. Bubble baths, use of antibiotics and the presence of a contraceptive device (like IUD) can also alter the vaginal pH leading to BV.

How is bacterial vaginosis diagnosed?

BV has signs and symptoms like foul-smelling/fishy vaginal odor and thin, watery, greenish, gray or whitish vaginal discharge which makes one suspect the possibility of having bacterial vaginosis. Other symptoms are painful urination and vaginal itching. Some tests are afterward conducted by a doctor to make a clinical diagnosis of bacterial vaginosis.

How can I prevent bacterial vaginosis?

Prevention of BV is quite easy. You just need to let go of those factors that can make you have bacterial vaginosis. Some preventive tips include:

  • Avoid smoking
  • Do not practice vaginal douching. Stay off vaginal deodorants and over-the-counter vaginal products.
  • Use only clean water to wash your vagina
  • Avoid unnecessary use of antibiotics which can kill the normal vaginal flora
  • Use condoms
  • Multiple sexual partners and sharing of sex toys should be discouraged
  • Take shower- baths and not bubble tub baths
  • For tub baths, avoid scented, shampoo or body wash in the tub.
  • Do not use strong detergents for your underwear

When should I see a doctor?

You should see a doctor once you think you have bacterial vaginosis. If you have any unusual vaginal discharge, some abnormal vaginal odor or you've treated yeast infection with no resolution of symptoms, you need to see your doctor.


Bacterial vaginosis is an infection that can affect the vaginal tract of cis- and trans-females. It occurs as a result of over growth of vaginal bacterial flora. With symptoms and tests, a proper diagnosis is made and treatment can lead to a complete recovery. Prevention is linked to avoiding triggers and risk factors.


  1. Kairys N, Garg M. Bacterial vaginosis. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 [cited 2023 Aug 17]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK459216/
  2. Coudray MS, Madhivanan P. Bacterial vaginosis—A brief synopsis of the literature. European Journal of Obstetrics & Gynecology and Reproductive Biology [Internet]. 2020 Feb 1 [cited 2023 Aug 17];245:143–8. Available from: https://www.sciencedirect.com/science/article/pii/S0301211519306025
  3. Abou Chacra L, Fenollar F, Diop K. Bacterial vaginosis: what do we currently know? Frontiers in Cellular and Infection Microbiology [Internet]. 2022 [cited 2023 Aug 17];11. Available from: https://www.frontiersin.org/articles/10.3389/fcimb.2021.672429
This content is purely informational and isn’t medical guidance. It shouldn’t replace professional medical counsel. Always consult your physician regarding treatment risks and benefits. See our editorial standards for more details.

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Mary Mbam Chiamaka

Bachelor of Medicine, Bachelor of Surgery - MBBS, Medicine, Ebonyi State University, Abakaliki

My name is Mbam Chiamaka Mary. I am a Medical Doctor and health writer. Writing health articles have become a satisfying hobby for me as it excites me to see people enjoy the benefits of being properly informed about health and wellness. I hope reading this article helps your make better health choices.

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