Bacterial Vaginosis

What is BV?

Bacterial vaginosis, more commonly called BV, is an infection that develops in the vagina. It is the most common vaginal infection in women of reproductive age.^1,2 A change in the balance of bacteria that normally live in the vagina causes BV. Factors that change the balance include douching, taking antibiotics, wearing an intrauterine device (IUD), and having unprotected sexual activity, among others.

The most common symptom of BV is an increased vaginal discharge that usually has a "fishy" odor. The discharge is normally a milky white or gray color.¹ A woman may feel a burning sensation or, in rare cases, itching, when she urinates.

Sometimes a woman with BV has no symptoms. If you think you may be at risk of developing BV because you wear an intrauterine device (IUD) or because you have recently douched, taken antibiotics, or had unprotected sex, consider talking with your health care provider about getting checked for BV. For more details about factors that increase risk for BV, see What causes BV?

A change in the balance of bacteria that normally live in the vagina causes BV.^1,2,3

Usually, "good" bacteria (lactobacilli) outnumber "bad" bacteria (anaerobes) in your vagina. But if anaerobic bacteria become too numerous, they upset the natural balance of microorganisms in the vagina and lactobacilli decrease.

Factors that can disrupt the balance of bacteria in the vagina include:

• Reacting to antibiotics
• Using an intrauterine device (IUD)
• Having unprotected sex with one or more partners
• Douching

Diagnosis of BV requires a vaginal exam by a qualified healthcare provider and the laboratory testing of fluid collected from the vagina.^1,2,3

An examination to diagnose BV is similar to a regular gynecological checkup. While performing the examination, your healthcare provider will visually examine your vagina for signs of BV, which include increased vaginal discharge that has a white or gray color.

Your healthcare provider will also collect a small amount of your vaginal fluid with a wooden spatula or cotton-tipped applicator. The sample will be tested in a laboratory for the diagnosis of BV.

An accurate diagnosis of BV is important because it will help the provider determine whether you have BV or some other infection, such as a sexually transmitted disease like chlamydia.

To ensure an accurate diagnosis, healthcare providers usually ask that you:

• Do not douche for 24 hours before your exam.
• Do not use anything that might irritate your vagina, like vaginal sprays.
• Do not have sex during the 24 hours before your exam.
• Do not put anything in your vagina, including a tampon, before seeing the health care provider.
• Do not schedule your examination while you are menstruating.

Yes, BV is usually curable with prescription antibiotics that can help readjust the balance of bacteria in the vagina. Although some over-the-counter vaginal medications are sold, these are not effective for curing BV. Currently, only prescribed antibiotics are effective.

With BV, there is a risk of relapsing if the entire course of antibiotics is not finished.^1,2 Therefore, it is important to finish all of the pills in a BV prescription.

Although BV can be cured, it does carry certain risks. Women with BV are at a higher risk for:

• Delivering an infant preterm (before 37 weeks of pregnancy)
• Delivering an infant with a low birth weight (generally, 5.5 pounds or less)
• More easily contracting certain sexually transmitted diseases (STDs), including gonorrhea, herpes, and HIV/AIDS
• More easily infecting a partner with certain STDs, including HIV/AIDS
• Developing pelvic inflammatory disease

Currently, the only effective treatments for BV are prescribed antibiotics, including metronidazole and clindamycin.^1,2,3,4 These are prescribed as oral medications, which are taken by mouth, or as a gel or cream, both of which are inserted into the vagina with an applicator.

Even if symptoms start to disappear, it is important to complete the entire course of a prescription for BV because of the likelihood of recurrence.

Over-the-counter medications for treating vaginal problems are not effective for treating BV.

Should BV be treated in pregnant women?

According to the Centers for Disease Control and Prevention (CDC), pregnant women with BV should be treated because of the possible risks of BV to the fetus.

Risks of BV during pregnancy include delivering an infant preterm (before 37 weeks of pregnancy) and delivering an infant with a low birth weight (generally, 5.5 pounds or less).

The CDC recommends that pregnant women be tested—and treated if necessary—if they have symptoms of BV.

In addition, the CDC recommends that all pregnant women who have ever had a preterm delivery or delivered an infant with a low birth weight be considered for BV examination regardless of whether they have symptoms.

Some research shows that treating BV in pregnant women does not reduce the risk of preterm birth. Further study is needed to better understand these outcomes.⁵