What Is Bacterial Vaginosis (BV)? Causes, Symptoms, and Treatment

Bacterial vaginosis (BV) is an infection in your vagina. It’s one of the most common vaginal conditions in the world. In fact, it’s the number one cause of abnormal vaginal discharge in women in the U.S. ages 15 to 44. 

BV happens when certain bacteria in your vagina grow too much. All healthy vaginas have bacteria in them, mostly helpful ones called Lactobacilli. But if the Lactobacilli get outnumbered by other bacteria, it can lead to BV. 

Some people with BV don’t even know they have it. But others have bothersome symptoms, like itching, burning, and fishy-smelling vaginal discharge. And, if you have BV, it can put you at risk for other problems, too, like sexually transmitted infections (STIs), pelvic inflammatory disease, and pregnancy complications. 

Let’s take a closer look at BV symptoms, causes, and treatment — as well as what to know about whether your partner needs to be treated too. 

Bacterial vaginosis symptoms

Bacterial vaginosis symptoms can vary. More than half of people won’t know that they have it, while others can have various symptoms. 

If you have a BV infection, you may experience:

• A white or gray vaginal discharge, sometimes described as watery or foamy

• Vaginal irritation, including pain, itching, or burning

• Discomfort when urinating

• A foul smell, sometimes described as a fish-like odor 

Vaginal bleeding isn’t typically a symptom of BV. If you notice vaginal bleeding and a discharge, most likely there’s another explanation for your symptoms. 

What causes bacterial vaginosis?

Bacterial vaginosis is caused by an imbalance in your vagina’s natural bacteria (vaginal flora). As we mentioned above, a healthy vagina typically has lots of “good” Lactobacilli-type bacteria. There are also “bad” bacteria in the vagina called anaerobes, though not as many. 

One thing that Lactobacilli normally does is keep your vaginal pH low. When the levels of “good” bacteria and “bad” bacteria get off balance, the pH levels in your vagina start to go up. This allows the anaerobes to thrive and leads to BV symptoms.

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Is bacterial vaginosis a sexually transmitted infection (STI)?

Right now, the short answer is “no.” But it’s tricky, because we know that the bacteria that cause BV can be passed between sexual partners. In other words, though BV isn’t technically an STI, you can get it from having sex. And, even though BV only affects women, men can carry the bacteria that causes it.

So, why isn’t BV considered an STI then? There are two key differences: 

• First, BV isn’t caused by a single bacteria, like chlamydia or gonorrhea. It’s a shift in your overall vaginal flora. 

• And second, you can get BV in other ways too — without ever having sex. 

That said, the definition of what “is” and “isn’t” an STI continues to evolve. And since we know that BV is linked to sex — and to your sexual partners — it’s possible that it could be considered an STI at some point in the future. 

What are the risk factors for getting bacterial vaginosis?

Anybody with a vagina can get BV, but some people are more likely than others to get it. This includes people who:

• Are sexually active, including those who have multiple partners or a new partner 

• Have sex without a condom

• Have a copper intrauterine device (IUD) in place

• Smoke cigarettes

• Regularly douche or use scented soaps and baths

• Are pregnant

Studies show that some people may have differences in their vaginal flora that put them at risk for BV. We also know that Black women are roughly twice as likely to get BV compared to non-Hispanic white women. 

Bacterial vaginosis treatment

The first step to treating bacterial vaginosis is getting a diagnosis. You’ll need an in-person visit with a healthcare professional if you think you have BV. They’ll do a physical exam and collect a small sample of your vaginal discharge for testing. 

Anyone who tests positive for BV (whether or not you have symptoms) should be treated — including pregnant women. 

Bacterial vaginosis medication 

Bacterial vaginosis is treated with antibiotics. Common antibiotic treatments for BV include:

• Metronidazole (pills or vaginal gel) 

• Clindamycin vaginal cream 

Sometimes, people need more than one course of treatment to get rid of their symptoms. And about half of people with BV get it again within 12 months. So make sure to complete your full course of prescribed antibiotics and treatment, even if your symptoms improve.

Does my partner need to be treated for BV?

It’s possible. Your partner(s) should also be treated, according to the American College of Obstetricians and Gynecologists (ACOG), if the following are true:

• You’ve had BV (with symptoms) more than once. 

• You have sex with men. 

This means you and your partner(s) would both use medication for a week, and you’d take a break from having sex during that time. 

If you have same-sex partners, or it’s your first time having BV symptoms, the recommendations aren’t as clear. That’s because there hasn’t been research done in these groups of people yet. If you fall into one of these categories, ACOG guidelines are to talk it over with a healthcare professional and make the decision that’s best for your unique situation. 

Can untreated bacterial vaginosis go away on its own? 

Sometimes, people with bacterial vaginosis do get better on their own. But the longer symptoms are left untreated, the harder they can be to cure. 

Untreated bacterial vaginosis can lead to serious complications, such as higher risks of: 

• Getting other STIs, including HIV, from an infected partner

• Passing HIV to a sexual partner if you’re HIV positive

• Early labor, early delivery, and low infant birth weight with pregnancy

• Getting pelvic inflammatory disease

And untreated BV can increase the risk of infection after gynecological surgery. So women are often tested before surgery and treated if they test positive for the infection. 

How to prevent bacterial vaginosis

Here are a few things you can do to lower your risk of getting BV:

• If you have sex, limit the number of partners and use a condom or dental dam.

• Don’t douche or use scented soaps and baths.

• Wipe yourself front to back.

• Wash and keep clean any sexual props and toys.

• Quickly change out of wet clothes, such as bathing suits. 

• Wear cotton underwear that doesn’t trap moisture.

• Take probiotics.

But even if you try your best to prevent BV, sometimes it just sticks around. Try not to get discouraged, and talk with your gynecologist or primary care provider. You may need another course of antibiotics to treat it.

Bacterial vaginosis vs. yeast infection: What’s the difference?

BV and yeast infections can sometimes feel the same, but they’re different infections. However, you can have both infections at the same time.

Here’s a quick way to know the difference between BV and yeast infection. 

Quiz: Bacterial Vaginosis (BV) or Yeast Infection

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Written by:

Rebecca Horn, MD, MPH

Dr. Horn is a physician and public health specialist, with experience on four continents. She specializes in anesthesia and critical care and has a particular interest in perioperative care, as well as obstetric anesthesia.

Edited by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. A pulmonologist and hospitalist, she practiced and taught clinical medicine at hospitals in London for a decade before entering a career in health education and technology.

Reviewed by:

Sarah Gupta, MD

Sarah Gupta, MD, is a licensed physician with a special interest in mental health, sex and gender, eating disorders, and the human microbiome. She is currently board certified by the American Board of Psychiatry and Neurology.

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