Bacterial Vaginosis

Medically Reviewed by Jabeen Begum, MD on January 22, 2024
12 min read

Bacterial vaginosis (BV) is an infection of the vagina. It results from a change in the normal balance of vaginal bacteria.

BV is a very common vaginal infection. About 35% of people with a vagina will get BV at some point. Rates are even higher among Black people with a vagina, with close to 50% getting BV.

BV usually doesn't cause any other health problems. But it can lead to issues, especially when you're pregnant or trying to get pregnant.

BV vs. yeast infection

BV isn’t the same as a yeast infection. BV is caused by bacteria, while a yeast infection results from a fungus called candida, which is also known as yeast.

These infections happen when the healthy levels of bacteria or yeast in the vagina get out of balance. Both BV and yeast infections cause increased vaginal discharge and require treatment. You usually can tell the infections apart due to your symptoms, but not always.

Typically, BV has a fishy smell. A yeast infection usually has no odor and involves a thick, white discharge, itchiness, burning, and pain when peeing.

Your doctor will give you an antibiotic for BV. Yeast infections can be treated using over-the-counter medications.

Is bacterial vaginosis an STD?

BV is not a sexually transmitted disease (STD) or a sexually transmitted infection (STI). But people who are sexually active, particularly those with more than one sex partner, are more likely to get BV. People who do not have vaginas and people who are not sexually active rarely get BV.

You might feel embarrassed to have BV. But know that it is very common, can be treated by your doctor, and is not caused by anything you did wrong.

About half of the time, people with BV have no symptoms. But they can include:

  • Pain, burning, or itching in the vagina
  • Burning sensation when you pee
  • Fishy smell that gets stronger after sex
  • Thin white, gray, or green discharge
  • Stomach pain
  • Higher vaginal pH

Bacterial vaginosis discharge

Not everyone with BV has vaginal discharge. If you do, it is usually thin and watery. The color can be white, gray, or greenish.

Bacterial vaginosis smell

You can have BV and not notice any change in vaginal odor. But often, there is a fishy or foul-smelling odor, especially after sex.

Because BV symptoms can look like those from other infections, it’s important to find out the cause. See your doctor if you:

  • Have a new vaginal dischargealong with a smell, itchiness, pain, or a fever 
  • Have more than one intimate partner or a new partner (if so, you might need to be checked for an STD or STI)
  • Used an over-the-counter medicine for a yeast infection but still have symptoms


It's unclear exactly why BV happens. What is known is that a type of healthy bacteria called lactobacillus keeps your vagina slightly acidic, which prevents the growth of bad bacteria. If your lactobacillus levels drop, more bad bacteria move in, and you get BV.

Is bacterial vaginosis contagious?

BV is not contagious, except during sex if both partners have vaginas. People who are sexually active are more likely to get BV. It’s not known why or how sex increases the risk of BV.

You can not get it from sharing bedding, towels, or clothing with someone who has BV.

Is BV a sign of cheating?

Having BV does not mean that you or your partner are cheating. But if you have more than one sex partner, you are more likely to get BV. Sexual activity, with the same or a different partner, can change the pH or balance of bacteria in the vagina, making BV more likely.

Why do I keep getting bacterial vaginosis?

If you keep getting BV, you’re not alone. Researchers aren’t sure why, but recurrent BV is very common. Nearly 50% of people with BV will get it again within one year.

Not clearing the original infection may be to blame. You can reduce your risk of having BV in the future by using condoms, not douching, keeping sex toys clean, and reducing your number of sex partners.

Anyone with a vagina can get BV, but your risks are higher if you:

  • Smoke.
  • Are sexually active. Being sexually active is a risk factor, especially if you don’t use condoms or dental dams. BV isn’t sexually transmitted, but researchers think that sex may change the balance of bacteria in your vagina, which makes an overgrowth of unhealthy bacteria more likely.
  • Use a douche. Douching upsets the natural balance of bacteria. So can scented soaps, bubble baths, and vaginal deodorants.
  • Have a new or multiple sex partners. Having a new sex partner, or more than one, makes it more likely for you to develop BV. It isn’t clear why, but people with vaginas who have female partners are most at risk. You can get BV from oral, vaginal, and anal sex.
  • Are in your reproductive years. Children and people who have never had sex or who are not sexually active rarely get BV. More research is needed to know how common BV is after menopause.
  • Use an intrauterine device (IUD). Using an IUD, which is a form of birth control that fits inside your uterus, has also been linked to BV, especially if you have irregular bleeding. But it isn’t clear whether it’s a direct cause.
  • Have a naturally low level of lactobacilli bacteria in your vagina.
  • Are taking antibiotics.

You can’t get vaginal infections like BV from swimming pools or public toilet seats.

You're more likely to get BV during pregnancy due to the hormonal changes that happen in your body while expecting. If you have BV during pregnancy, it’s very important to treat it. Some research shows that BV is linked to an increased risk of certain pregnancy-related complications, such as:

  • Delivering your baby early (preterm birth), which can lead to issues for your baby, such as low birth weight and breathing problems
  • Your water breaking early (early rupturing of your amniotic sac)
  • Miscarriage

Some new studies point to other causes of these issues. But more research is needed as pregnant people with BV do have higher rates of pregnancy complications.

Having BV while pregnant can also put you at risk for chorioamnionitis, which is inflammation of the membranes surrounding the baby in utero. This increases your chance of early delivery. A newborn who survives this kind of delivery has a higher-than-normal risk of cerebral palsy, a disorder that affects your baby’s ability to move and maintain balance and posture.

To confirm a BV diagnosis, your doctor will:

  • Ask about your medical history
  • Do an overall physical exam
  • Do a pelvic exam
  • Check your vagina’s pH or acidity level
  • Take a sample of discharge from your vagina to look for cells covered with bacteria

Tests for BV

Your doctor can check your vaginal discharge for BV. These tests include:

  • Wet mount or vaginal smear. This test looks at a sample under a microscope to check for infection.
  • Whiff test. Vaginal fluid is mixed with a chemical that produces a strong, fishy smell if you have BV.
  • Vaginal pH. The acidity of your discharge is checked. A high reading is a sign of BV.
  • PCR test. This test looks for DNA from harmful bacteria and costs more, so it is not used very often.

Home test kits

There are many BV home test kits on the market. They are not always accurate. Your best bet is to get checked by your doctor. But when used correctly, some tests are close to 90% reliable.

There are a variety of medications your doctor may prescribe to treat BV. Even if you don’t have symptoms, it’s important to know how to get rid of BV.

Untreated bacterial vaginosis

BV will sometimes go away on its own. More often though, the infection will continue or get worse. BV may also come back if it isn’t fully treated. Untreated BV is most harmful during pregnancy but increases the risk of STIs and can cause irritation, discharge, and a strong vaginal odor.

Bacterial vaginosis medication

To treat BV, your doctor can prescribe antibiotics, which could be in the form of a tablet or granules you take by mouth, or an ovule suppository, cream, or gel you put into your vagina.

These medications include:

  • Clindamycin, a cream you use in your vagina. It sells under the brand names Cleocin and Clindesse. Don't rely on condoms for birth control with this medication, as it can weaken latex condoms not only while you’re taking it, but for at least 3 days after you stop. 
  • Metronidazole, available as a pill you swallow or a gel you insert in your vagina. This medication sells under the brand names Flagyl and Metrogel-Vaginal.
  • Secnidazole, available as a single pill you take once. It’s sold under the brand name Solosec.
  • Tinidazole, available as a pill you swallow. It’s sold under the brand name Tindamax.

Metronidazole, secnidazole, and tinidazole won’t affect the birth control pill or patch. However, they can cause nausea or stomach pain, especially if you drink alcohol during or 1-3 days after treatment. It’s recommended to avoid drinking alcohol with these medications.

BV can get worse after having sex. So, avoid sexual contact until you're done taking your medicine and your symptoms are gone. 

You'll need to take most treatments for 5-7 days. Complete your entire course of medication, even if the symptoms go away. If you stop early, the infection could come back.

If your partner also has a vagina, they may want to see their doctor to find out if they need treatment. Partners with a penis do not need to be treated.

You should always talk to a doctor before trying to treat BV at home. Some home treatment methods that may help include:

Probiotics. You find these live bacteria in some foods such as yogurt, sauerkraut, or kefir. You can also take probioticsas a supplement. They may help balance out the bacteria in your vagina and treat your BV.

There are at least seven types of bacteria that grow in the vagina. Lactobacillus is one of them. BV is linked to a decline in lactobacillus levels, which is found in yogurt and acidophilus milk. Some studies suggest that eating foods that contain lactobacillus may be beneficial, but more research is needed.

Do not douche with yogurt or any other product. Vaginal douching is a risk factor for BV.

Garlic supplements. A very small study on 120 women showed that taking a garlicsupplement for 7 days worked as well as an antibiotic to relieve symptoms of BV.

Vitamin C. Some studies have shown that taking a daily 250 mg vitamin C supplement may help improve your vaginal pH (the measure of acidity or basicity) and increase the levels of healthy bacteria. It may also work to help prevent BV from coming back.

Boric acid for BV

Your doctor may recommend boric acid suppositories you put in your vagina. You can buy these over the counter. Boric acid can help rebalance the acid in your vagina and relieve itching and burning. There is not much research on using boric acid to treat BV or on the safety of its long-term use. But when combined with antibiotic medications, it can help clear infections, particularly for people with recurrent BV.

Hydrogen peroxide for BV

Rinsing your vagina with hydrogen peroxide may help reduce BV symptoms, treat infection, and prevent reoccurrence. Healthy vaginal bacteria produce hydrogen peroxide, which keeps bad bacteria in check. Research shows washing with hydrogen peroxide for 7 days can regulate vaginal pH and prevent BV from coming back. Check with your doctor to find out if this remedy is right for you.

Bacterial vaginosis, especially if you don’t treat it, has been tied to a higher risk of other health problems. These include:

  • A bacterial infection, if you have a hysterectomyor other surgery on your organs while you have BV

  • A sexually transmitted infection such as herpes, chlamydia, or gonorrhea, or passing HIV to your partner. There is increased HIV shedding in people with HIV when they have BV, making transmission more likely. You are also more likely to get HIV during sex from your partner if you have BV.

  • Less success with fertility treatments such as in vitro fertilization(IVF)

  • Increased risk of blockage in your fallopian tubes, preventing sperm and egg from meeting (which lowers your chance of getting pregnant)

  • Pelvic inflammatory disease (PID), an infection of the uterus, fallopian tubes, and ovaries

Sometimes, BV comes back after treatment and can even become chronic. As many as 50% of people who have BV will have a recurrence. This may happen if:

  • You’re resistant to treatment
  • Treatment didn’t clear the whole infection
  • You are reinfected by new sexual partners

Even after BV is treated and goes away, it often returns. If that happens, you'll probably need to take antibiotics again for a longer time.

They may prescribe extended-use metronidazole.

If you use an IUD, and BV keeps coming back (recurrent BV), you may want to talk to your doctor about a different type of birth control.

To lower your chances of getting BV, take these steps:

  • Clean sex toys after every use.
  • Get tested for STDs, and make sure your sex partners are tested.
  • Limit your number of sex partners.
  • Use a condom or dental dam during sex.
  • Use only water or mild unscented soap to wash your vagina.

To help maintain a healthy pH in your vagina:

  • Don’t douche.
  • Avoid antiseptic bath products such as antibacterial soaps, which can cause an imbalance in the bacteria in your vagina.
  • Wipe from front to back after you use the bathroom. If you wipe the other way, bacteria from your poop could get into your vagina and disrupt your vaginal balance.
  • Wear cotton or cotton-lined underwear. Less breathable fabrics trap moisture and increase heat, making bacteria growth more likely.
  • Avoid scented menstrual products, which can increase vaginal pH.

If you suspect you have BV, contact your doctor to get tested. Ask about any other remedies you can try in addition to taking antibiotics. Avoid sex until your infection clears and contact your doctor if you notice signs of recurrent BV.

Can bacterial vaginosis go away on its own?

BV can sometimes go away without treatment; however, it's important to be seen if you have symptoms, as you can have pregnancy complications and increase your risk of STDs

Is bacterial vaginosis contagious?

BV is not contagious, except it can be passed during sex between people who have vaginas.

What do BV sores look like?

BV does not cause vaginal sores. If sores are present, you may have another type of infection such as herpes or genital warts.

Why does my boyfriend keep giving me BV?

Having sex increases your risk of BV because it can disrupt your vaginal balance. Although men and people assigned male at birth (AMAB) can't get BV, they can spread the bacteria, getting BV from one sexual partner who is a woman/person assigned female at birth (AFAB) and carrying it to another partner who is a woman/AFAB.  Studies show that a woman or person AFAB who has an ongoing male (AMAB) partner is twice as likely to get recurring BV; and not using a condom regularly during penis-in-vagina sex is linked to higher rates of recurring BV.