Bacterial Vaginosis


Bacterial Vaginosis (BV) is a bacterial infection in the vagina that occurs when there is an imbalance in the bacteria that are normally present.1 It occurs frequently in women of reproductive age, and is the most common vaginal infection in women aged 15 to 44. BV often recurs in women who get it, with 30% of females having a recurrence within a month of treatment and 50% of females having a recurrence within a year.2

Symptoms of BV include thin, white or gray vaginal discharge, pain or itching in the vagina, a strong fish-like odor, and painful urination. Though BV symptoms can sometimes clear up on their own, see a doctor if you are experiencing them because only a medical professional can diagnose your symptoms and provide you with information on the best possible treatment. Although BV is more common in sexually active women, it is not a sexually transmitted infection (STI).3 This article contains information on the symptoms and causes of BV, and recommended options for treatment.

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Causes of BV

Doctors and researchers are not completely sure what causes BV or how some females get it. It is linked to an imbalance of healthy bacterias in the vagina, and is often caused by gardnerella vaginalis, the most common type of bacteria in your vagina.1 Certain activities such as douching, acquiring a new sexual partner, or having multiple sexual partners can increase a female’s risk of acquiring BV by upsetting the balance of bacteria in the vagina.3

BV and Sex

Although it is not considered an STI, there is a link between BV and sexual activity. BV rarely occurs in women who have never had sex, and women who have a new sexual partner or multiple sexual partners are more likely to get it.3

There is no research to show that treating a sexual partner affects whether or not a woman gets BV. However, having BV can increase your chances of getting other STIs. These include HIV, chlamydia, and gonorrhea.3 Having BV can also increase your chances of passing these STIs to a partner if you have them.

Women who currently have a BV infection are free to engage in sexual activity if they wish, but should take precautions before doing so. Because of the increased risk of transmitting STIs, it is especially important to use a barrier method of protection, such as a condom, during intercourse. Additionally, the physical discomfort caused by BV symptoms may make intercourse painful or uncomfortable. Women with BV who wish to have intercourse before the infection has subsided should communicate with their partners and let them know what they can do to help make the experience less painful. Some ways to reduce pain during intercourse are using plenty of lubrication and engaging in foreplay before intercourse.4

A couple holding hands.


BV is often accompanied by several noticeable symptoms that you can identify and bring up to your doctor in order to diagnose the condition. However, there are several other conditions that present symptoms similar to those of BV. This section provides an overview of the common symptoms of BV, as well as some other infections that could be confused with BV. It is important to see a doctor if you notice any of these symptoms occurring, since only healthcare professionals can definitively diagnose your symptoms and recommended treatment.

Symptoms of BV may include the following:3

  • A thin white or gray vaginal discharge;
  • Pain, itching, or burning in the vagina;
  • A strong fish-like odor, especially after sex;
  • Burning when urinating;
  • Itching around the outside of the vagina.

These symptoms, or similar symptoms, can also be present as a result of conditions that are not BV. Yeast infections are one of the most common conditions with symptoms similar to those of BV. The symptoms of a yeast infection include itching around the vagina, pain during sex or urination, and a thick white discharge.5 This discharge is one of the most noticeable differences between the symptoms of BV and a yeast infection. The discharge with BV may be white or gray and have a fishy smell, whereas the discharge with a yeast infection may also be white or gray but is more likely to resemble cottage cheese.6

Chlamydia and gonorrhea are STIs with symptoms that can resemble the symptoms of BV. Some of the symptoms of chlamydia in females include pain during urination or sex, bleeding between periods, lower belly pain, and abnormal discharge. The discharge from chlamydia is often yellowish in color and can have a strong scent, as opposed to the white or gray discharge of BV.7 Gonorrhea symptoms include painful or burning urination, bleeding between periods, or an abnormal discharge that can appear yellow or bloody.8

Treatment for BV

If you notice any of the symptoms of BV described above, it is important to see a doctor and inform them of your symptoms so that you can receive proper treatment. At your medical visit, be sure to inform your doctor of all the symptoms you have and how long they have been present. A health care provider will examine your vagina for signs of vaginal discharge. Your provider can also perform laboratory tests on a sample of vaginal fluid to determine if BV is present.3

A doctor talking to a client. They are sitting across from each other.

If your doctor determines that you do have BV, they can prescribe antibiotics to restore the balance of bacteria in your vagina and clear the infection. When taking antibiotics, it is essential to take all of the medicine prescribed to you, even if your symptoms subside before the course of medication is over. Contact your doctor or pharmacist if you have any questions about the proper way to administer your antibiotics.3

Health Risks Associated With BV

Some people may think that the symptoms of BV are not severe enough to warrant a doctor’s visit and treatment, but there are a number of health risks that can occur as a result of BV if it is left untreated. One of these risks is that females with BV have an increased chance of contracting an STI such as HIV, gonorrhea, or chlamydia if they engage in sexual activity with an infected partner. Women with BV are also more likely to pass an STI to a partner.3

Pregnant women are especially at risk for complications with BV. Women who have BV during pregnancy are more likely to give birth prematurely, and the newborn is more likely to be underweight at birth.3

A person's hands forming a heart on a pregnant belly.

Concluding Remarks

Bacterial vaginosis is one of the most common vaginal infections in sexually active females, and can be easily diagnosed and treated by a medical professional. If you develop any of the symptoms of BV, you should make an appointment with a doctor who can conduct an examination and determine what you have and the best course of treatment. Although it may seem like a minor discomfort, BV does present risks such as an increased likelihood of transmitting STIs and complications with pregnancy. For these reasons, it is important to seek medical care if you believe you might have BV.


  1. Parenthood, Planned. “What Is Bacterial Vaginosis? | Symptoms, Signs and Causes.”Planned Parenthood
  2. Bradshaw, Catriona S., et al. “High Recurrence Rates of Bacterial Vaginosis over the Course of 12 Months after Oral Metronidazole Therapy and Factors Associated with Recurrence.” The Journal of Infectious Diseases, vol. 193, no. 11, 2006, pp. 1478–1486.
  3. “Bacterial Vaginosis – CDC Fact Sheet.”
  4. “Sex During Vaginal Infection: Is It Harmful?”
  5. Vaginal Yeast Infections.”
  6. “Bacterial Vaginosis.”
  7. Parenthood, Planned. “What Are the Symptoms & Signs of Chlamydia?” Planned Parenthood.
  8. Parenthood, Planned. “What Are the Symptoms & Signs of Gonorrhea?” Planned Parenthood.

Last Updated: 26 February 2018.