Bacterial vaginosis (BV) is a mild infection in the vagina. It happens when there are more "bad" bacteria than "good" bacteria.

What Are the Signs & Symptoms of Bacterial Vaginosis?

Symptoms of BV include:

• thin white or gray vaginal discharge (a fluid that comes from the vagina)
• a fishy smell from the vagina, mostly during a period or after sex

Itching and burning aren’t common signs of BV. So if you have those symptoms, your doctor will check for other conditions.

What Causes Bacterial Vaginosis?

Both good and bad bacteria live in the vagina. When there are fewer good bacteria than usual, more bad bacteria grow. This can cause symptoms of BV.

Although doctors don't know for sure what causes BV, some things can make it more likely to happen. These include washing out the vagina, smoking, or having more than one sexual partner or a new one. BV is more common in people who have had sex, although it's not an STD and doesn’t always spread from one person to someone else.

You can't get BV from things like toilet seats, sheets, towels, or swimming pools.

How Is Bacterial Vaginosis Diagnosed?

The doctor will ask questions about your health and symptoms, do an exam, and maybe do a pelvic exam to look inside your vagina. A sample of vaginal fluid will be needed, and this is collected with a swab to test in the office or a lab.

How Is Bacterial Vaginosis Treated?

The usual treatment for BV is antibiotics (medicine that fights bacteria). These come as pills you swallow or gels or creams you put in your vagina.

Because BV can come back, your doctor may need to prescribe antibiotics more than once. Even if you feel better before you’re done taking them, be sure to use the rest just as your doctor says. That's the best way to kill the harmful bacteria.

Can Bacterial Vaginosis Be Prevented?

You can’t always prevent BV. But you can lower your chances of getting it by not using vaginal sprays, products to wash out the vagina, or body spray near the vagina.

You can also help prevent BV by not having sex. If you do have sex, limit the number of partners. Also, use a condom, finger condom, or dental dam each time you have sex. This helps protects you from getting a sexually transmitted disease (STD) too.

What Problems Can Happen?

When BV is properly treated, it often goes away without any problems, but it can come back. If it’s not treated, things like these might be more likely to happen:

• STDs like herpes, chlamydia, gonorrhea, or HIV
• pelvic inflammatory disease (PID), which can cause an infection or long-lasting belly pain
• problems during pregnancy, like giving birth too early or having a baby that’s too small

What Else Should I Know?

If you think you have BV, go to your doctor or a health clinic like Planned Parenthood. BV causes the same symptoms as some STDs, so your doctor can tell you what you have. If it’s BV and your sexual partner also has a vagina, they should get checked too.