Young woman with symptoms wondering what is bacterial vaginosis

What is Bacterial Vaginosis? Causes and Symptoms of BV

Medically reviewed on June 12, 2023 by Morgan Spicer, Medical Communications Manager. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.


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Have you heard of bacterial vaginosis (BV) and aren’t exactly sure what it is, or what causes it? Here’s your overview of bacterial vaginosis, including the causes, symptoms, and differences between BV and other vaginal infections.

What is BV?

Bacterial vaginosis is a condition impacting vaginal health. While commonly roped in with conversations about STDs, BV is not considered a sexually transmitted infection. [1] Bacterial vaginosis is considered the most common vaginal problem (occurring in up to 70%) for people assigned female at birth (AFAB) ages 15 to 44. [1-2]

What Causes Bacterial Vaginosis

BV is caused by an imbalance of the naturally occurring bacteria found in the vagina. [1] This bacteria is known as the vaginal flora and is a normal part of a healthy vagina. [3] The vaginal flora is necessary for keeping the vagina at a healthy pH and limiting the growth of unwanted organisms and yeast. [3] Anything that can disrupt the natural balance of pH and bacteria in the vagina can lead to BV. Some potential causes include sexual activity, douching, and antibiotic use. [1]

Who Can Get BV?

Anyone assigned female at birth can get BV. You do not have to be sexually active, although most people who get BV are. [1] Some people may be genetically predisposed to the overproduction of certain bacteria, which can put them at a higher risk of having BV. Other risk factors for getting bacterial vaginosis include [1-2]:

  • Pregnancy
  • Having a partner who is AFAB
  • Having new or multiple sex partners
  • Use of an intrauterine device (IUD)
  • Unprotected sex
  • Frequent douching
  • Cigarette smoking
  • Recent antibiotic use

While people assigned male at birth (AMAB) are unable to get bacterial vaginosis, they can spread the bacteria that causes BV. [2] Taking precautions with all partners when sexually active is the best way to protect yourself against STIs and other infections such as BV. This includes the use of condoms, dental dams, sanitizing sex toys, and so on. [1-2]

What Are the Symptoms of BV?

Not everyone that has BV will experience symptoms. In fact, up to 84% of people with bacterial vaginosis report not having symptoms. [1-2] Those that do experience symptoms may notice the following [1]:

  • Vaginal discharge that is off-white, gray, or slightly green
  • Painful urination
  • Painful sex
  • Foul-smelling discharge
  • Vaginal irritation or itching

Many BV symptoms are very similar to other infections. If you are noticing any of these symptoms or if you’re concerned about your sexual health, you should speak with a healthcare provider.

Diagnosing Bacterial Vaginosis

So how do you know if you have BV? As previously mentioned, only some people with BV will have symptoms. A healthcare provider will be able to help you determine if you have BV or any other infections, including a yeast infection or an STI. In order to diagnose BV, a healthcare provider will conduct a pelvic exam, take a sample of vaginal discharge, or perform other tests as necessary. [1] Testing vaginal fluid or examining fluid under a microscope will help measure vaginal pH and identify what bacteria may be present. [1]

Many providers use the Amsel criteria to diagnose bacterial vaginosis. When using this criterion, at least two to three out of four possible symptoms need to be present [1]:

  1. Thin white, yellow, homogeneous discharge
  2. The presence of clue cells under a microscope (cells of the cervix that have bacteria present)
  3. Vaginal fluid pH higher than 4.5
  4. Fishy odor after adding an alkali solution to a vaginal sample

Managing BV

About a third of cases can resolve on their own without medical treatment. [1] In other cases, antibiotics such as clindamycin or metronidazole can be used to treat BV. [1-2] Antibiotics can be in the form of oral tablets or vaginal creams. Taking antibiotics exactly as prescribed is important, meaning you should continue using the full dose of antibiotics that was given to you. Stopping treatment early may cause BV to return. [2] Most rounds of antibiotics will last around seven days and should eliminate the infection completely. In some cases, another round of treatment may be necessary. [1-2] While some cases of BV can resolve on their own, anyone experiencing symptoms may still benefit from speaking to a healthcare provider to rule out other infections. [1-2]

Potential Complications

There are some potential complications associated with bacterial vaginosis, especially if left untreated. Failure to treat BV may lead to fertility and pregnancy complications, including pelvic inflammatory disease (PID), miscarriage, and premature birth. [1-2] BV also increases your risk of STIs, including HIV. If someone is living with HIV and gets BV, they may be at a higher risk of passing HIV to sexual partners. [1-2] Research shows that BV nearly doubles the risk of chlamydia or gonorrhea infection. [1]

The Differences Between BV and Other Infections

BV is often talked about in relation to other vaginal infections, including yeast infections, urinary tract infections, and STIs. While some of the symptoms of these infections can be similar, there are some key differences you should know. An STI is an infection that occurs as a result of bacteria or other pathogens not normally found in the vagina. [4] A yeast infection is caused by an overgrowth of yeast in the vagina. [5] Urinary tract infections (UTIs) are caused by bacteria reaching the urethra and bladder. [6] Yeast infections, UTIs, and BV are not sexually transmitted, however, being sexually active may be a risk factor for these conditions. [5-6] Symptoms of these infections can overlap, but here are some key differences to note [1,4-6]:

  • A yeast infection may cause thick, white discharge and may cause itching or burning in the vagina and around the vulva
  • A UTI may cause painful urination or a frequent and intense urge to urinate
  • BV may cause a fishy vaginal odor and gray or slightly green discharge
  • STIs may cause swelling near the genitals, bumps, sores, or warts near the mouth, genitals, or anus.

Many of these symptoms can overlap and may even be a result of another type of infection. If you are noticing symptoms, it’s important to speak to a healthcare provider right away.

Sexual Health Testing With Everlywell

Bacterial vaginosis is the most common vaginal condition experienced by people AFAB and of reproductive age. BV is typically not a serious condition, but if left untreated, may cause severe complications down the line. Many people with BV don’t experience symptoms, however, BV can cause symptoms such as fishy vaginal odor, abnormally colored discharge, painful sex, painful urination, or vaginal irritation. If you are sexually active or have concerns about your sexual health, Everlywell can help. Book a women's telehealth consultation to discuss your concerns with a healthcare provider, or shop for various at-home sexual health tests.

Is Bacterial Vaginosis an STD?

What Happens if BV Goes Untreated?

BV vs. UTI: The Differences Explained

How to Treat Bacterial Vaginosis (BV): Medications and Home Remedies

How to Prevent BV: Methods for Preventing Bacterial Vaginosis


References

  1. Kairys N, Garg M. Bacterial Vaginosis. [Updated 2022 Jul 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459216/
  2. Bacterial Vaginosis. Cleveland Clinic. February 6 2023. URL. Accessed June 9 2023.
  3. Miller EA, Beasley DE, Dunn RR and Archie EA (2016) Lactobacilli Dominance and Vaginal pH: Why Is the Human Vaginal Microbiome Unique? Front. Microbiol. 7:1936. doi: 10.3389/fmicb.2016.01936
  4. Garcia MR, Leslie SW, Wray AA. Sexually Transmitted Infections. [Updated 2023 May 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560808/
  5. InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. Vaginal yeast infection (thrush): Overview. 2019 Jun 19. Available from: https://www.ncbi.nlm.nih.gov/books/NBK543220/
  6. Bono MJ, Leslie SW, Reygaert WC. Urinary Tract Infection. [Updated 2022 Nov 28]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470195/
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