Bacterial vaginosis is common in people with a vagina. Although it can clear up on its own, getting treatment can lower your risk of complications and health risks.

A healthy vagina naturally contains both “good” and “bad” bacteria. But if there’s an overgrowth of bad bacteria, an infection called bacterial vaginosis (BV) can occur.

BV commonly affects people with a vagina between ages 15 and 44. Typically, it develops in people who are sexually active.

According to the Centers for Disease Control and Prevention (CDC), BV is the most common cause of vaginal symptoms among women ages 14–49 in the United States.

In the National Health and Nutrition Examination Survey, 2001–2004, prevalence of BV was about 29% of females ages 14–49, or about 21 million individuals. Prevalence means the number of people affected by a condition at a particular time. Although this survey is older, it provides the most current reliable nationwide count.

Research indicates that BV affects about 1 in 3 women worldwide. Global prevalence of BV varies greatly, ranging from 4–74% of women, according to research from 2022. Bacterial vaginosis is most common in parts of Africa and least common in Asia and Europe.

Here are the top causes and treatments for bacterial vaginosis plus tips for how to prevent bacterial vaginosis.

Symptoms

An excess of bad bacteria throws the vaginal environment out of balance, resulting in symptoms like:

  • thin grayish-white discharge, especially after sexual intercourse
  • discharge with a fishlike odor
  • pain during urination
  • pain during or after sexual intercourse
  • vaginal itching

In some cases, BV causes no symptoms. Experts don’t know exactly what causes BV.

Causes

According to the CDC, BV is more common in people who are sexually active. However, researchers do not understand exactly why.

A 2023 study suggests that the bacteria causing BV may be transferrable from women to men during sex, and researchers are exploring whether men can transmit it to women.

One study shows that the bacteria causing BV can live on the penis or in a man’s urinary microbiome. In the study, a significant number of women developed BV within 6–12 months after having sex with men, suggesting that bacteria associated with BV were transmitted to the women during sex.

Factors that may increase your risk of BV include:

  • douching
  • not using condoms
  • having multiple sex partners
  • having new sex partners

Although BV can’t always be prevented, you can take the following precautions against BV:

Diagnosing bacterial vaginosis

To diagnose BV, a healthcare professional will start by taking a medical history and doing a physical pelvic exam. They will take a sample of vaginal secretions and order lab tests analyzing your vaginal cells and checking for vaginal acidity. Sometimes, clinics do these tests in the office.

Home test kits are available in drugstores, but they are not always accurate. These tests check for symptoms of BV, like changes in vaginal acidity and by-products of a BV infection rather than for BV itself.

Home test kits might indicate whether you have BV. But you’ll want to confirm your results with a healthcare professional. They can help you decide on the best treatment.

Prescriptions for BV

Metronidazole

  • Potential side effects: nausea, vomiting, diarrhea, metallic taste in the mouth, other gastrointestinal symptoms, appetite loss, headache, mouth or tongue irritation
  • Pros: effective treatment; easy to take
  • Cons: higher price point; has many potential side effects

One of the best prescription treatments for BV is an antibiotic called metronidazole. You can take it as a pill or gel.

The CDC recommends the following dosages:

  • Pill: 500 milligrams (mg) taken orally twice per day for 7 days
  • Gel: 5 grams (g) inserted into the vagina once per day for 5 days

If you have BV that recurs, a doctor may prescribe 500 mg of oral medication for 10–14 days. Another option is to use vaginal gel for 10 days, then twice weekly for 3–6 months.

Clindamycin

  • Potential side effects: nausea, vomiting, joint pain, heartburn, pain when swallowing, vaginal discharge, metallic taste in the mouth, itching or burning of the vagina
  • Pros: effective prescription treatment; available in several different forms
  • Cons: higher risk of colitis than other antibiotics; creams and ovules may weaken certain forms of contraception

Clindamycin is another effective prescription treatment for BV. It’s an antibiotic that you can take as:

  • a pill
  • cream
  • ovule suppository

An ovule suppository is a medication membrane that melts inside the vagina.

According to the CDC, the recommended dosages for clindamycin are:

  • Pill: 300 mg taken orally twice per day for 7 days
  • Cream: 5 g inserted into the vagina at bedtime for 7 days
  • Ovule suppositories: 100 mg inserted into the vagina at bedtime for 3 days

Clindamycin cream and ovules contain oil, which may weaken latex products like condoms and diaphragms. This effect can last 72 hours for ovules and 5 days for cream.

Tinidazole

  • Potential side effects: metallic taste in the mouth, loss of appetite, vomiting, nausea, constipation, stomach pain or cramping, tiredness, dizziness, headache
  • Pros: easy to take; short course; lower cost than other prescription options
  • Cons: potential side effects

It’s possible to develop adverse side effects from metronidazole or clindamycin. In this case, the doctor may prescribe tinidazole instead.

Tinidazole is also an antibiotic that you can take as a pill. For BV, there are two recommended dosages:

  • 2 g orally once per day for 2 days
  • 1 g orally once per day for 5 days

Secnidazole

  • Potential side effects: nausea and vomiting, diarrhea, headache, metallic taste in the mouth
  • Pros: requires a single dose; easy to mix into food
  • Cons: higher price point

Another option is secnidazole. This is an antibiotic that you can take in one dose.

Secnidazole is available as granules that you can consume orally. The recommended single dose is 2 g. You can take the granules by mixing them with unsweetened applesauce or yogurt first.

Secnidazole is significantly more expensive than other treatments. However, it may be a good option if you prefer a single-dose treatment.

Other remedies for BV

Probiotics

  • Potential side effects: mild gastrointestinal side effects
  • Pros: cost-effective; limited side effects; may help prevent and treat BV; available in fermented food, pill, or liquid form
  • Cons: not as effective as other methods

Probiotics are good bacteria. Taking probiotic supplements may help introduce healthy bacteria into your body.

According to a 2019 review of 10 studies, which focused on the effects of probiotics on bacterial vaginosis, there’s evidence that taking probiotic supplements daily may help treat and prevent BV.

And a research review from 2021 suggests that oral and vaginal probiotics may be an effective treatment and prevention option for BV. But researchers note that more studies are needed to determine:

  • correct dose
  • strain
  • length of treatment
  • whether probiotics should be paired with antibiotics

If you’ve been prescribed an antibiotic for BV, bear in mind that antibiotics can kill off the good bacteria as well as the bad. Probiotic supplements and yogurt can help replace good bacteria that are destroyed by antibiotics.

If you have BV, you could try taking probiotics daily to help treat and prevent future cases of this condition. Probiotics are available in:

You can buy probiotic supplements from:

  • pharmacies
  • health food stores
  • stores that sell supplements
  • online

Garlic

  • Potential side effects: burning if inserted vaginally
  • Pros: natural option; no prescription required; inexpensive
  • Cons: not as effective as prescription options

Garlic has strong antibacterial properties, and it’s long been used as a home remedy for BV.

For BV treatment, take garlic orally. Taking it vaginally has been known to burn vaginal tissue.

Research from 2020 looked at alternative treatments for BV. It concluded that taking a garlic supplement tablet could be an option for treating BV, although it also noted studies that suggest antibiotic treatment is more effective.

Boric acid suppository

  • Potential side effects: allergic reaction, vaginal irritation
  • Pros: safe to use as a vaginal suppository; as effective as some medical treatments
  • Cons: potential for allergic reaction or irritation; not safe to use during pregnancy

Boric acid vaginal suppositories are commonly used to treat BV, according to a research from 2019. According to the research, boric acid is typically effective at treating both BV and vaginal thrush, and few side effects occur.

Please note that boric acid is not edible — it’s toxic to eat. Store it away from children and animals. It’s also not safe to use if you’re pregnant. However, it’s considered safe to use boric acid in the vagina.

According to the CDC, experts still don’t fully understand how BV spreads. But in general, anything that changes the chemical balance in your vagina can increase your risk of BV.

For instance, these steps may lower your risk of BV:

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Although BV can clear up on its own, there are times when it can get worse without treatment. Also, it has been associated with other serious health complications.

Considerations

  • Increased STI risk: If untreated, BV can increase your risk of contracting sexually transmitted infections (STIs), including HIV, chlamydia, and gonorrhea, according to a 2022 research review. BV may also increase the risk of contracting herpes simplex virus type 2 and the human papillomavirus.
  • HIV transmission: Research shows that BV can cause up to six times more HIV shedding in someone who has HIV. Shedding refers to the amount of the virus present in bodily secretions. Increased shedding can put your sexual partner at a greater risk of contracting HIV during sex, even if you take medication for HIV. A 2018 study shows that women with both HIV and BV may be more likely to transmit HIV to their sexual partners than those with HIV.
  • Pregnancy complications: A 2016 study shows that BV can trigger a variety of potential complications for pregnant people. Researchers recommend testing and treatment of pregnant people who have symptoms of BV. Potential complications of BV during pregnancy can include:
    • miscarriage
    • preterm labor
    • infants with low birth weight
    • placenta and amniotic fluid infection (chorioamnionitis)
    • postpartum endometritis
    • pelvic inflammatory disease after abortion
  • Increased risks to sexual partners: Research is still undecided on whether bacteria associated with BV can be transmitted by both men and women to their partners during sex. It appears likely that transmission can occur when people with a vagina have sex, and some researchers say transmission may also occur during heterosexual sex.

If your symptoms haven’t resolved or started to clear up after a week of treatment, you can make an appointment with a doctor or gynecologist.

Also, contact a doctor if you have:

Consider making an appointment on a day when you won’t have your period. This allows the doctor to take a swab of your vaginal discharge for testing.

You can book an appointment with an OB-GYN in your area using our Healthline FindCare tool.

Recurring BV

Recurring BV is common. Even with treatment, infections recur in more than 50% of cases within 6 months to 1 year. The reasons for this high recurrence rate are not known.

Research is divided on whether recurrence can be caused by re-infection from partners during sex. The CDC says that although bacteria associated with BV can be found on male genitalia, treating male sex partners for BV has not helped prevent the recurrence of BV in women.

When both sex partners have a vagina, and one of them has BV, the infection often develops in the partner, according to the CDC. But research has not yet determined the effectiveness of treating people with a vagina to prevent BV recurrence.

Other possible causes of recurrence include:

  • antibiotic resistance
  • incomplete or unsuccessful treatment
  • imbalances in the vaginal microbiome

If symptoms recur soon after your treatment, you may want to see a healthcare professional to consider alternative treatments. Options include different or extended drug therapies or supplementation to restore normal flora balance in the vaginal microbiome.

Is bacterial vaginosis contagious?

BV is not considered to be an STI. But sex increases your risk of developing the infection.

If a person with BV has sex with a person with a vagina, their partner may need to seek treatment for BV.

What is the quickest way to treat bacterial vaginosis?

The fastest way to treat BV is to visit a doctor and get a prescription to treat the condition.

A prescription treatment will likely clear up your symptoms in 2–3 days. If you’re pregnant or undergoing any medical procedures, it’s especially important to have your BV taken care of sooner rather than later.

The doctor may prescribe an oral or vaginal antibiotic, like:

  • clindamycin
  • metronidazole
  • tinidazole

Can bacterial vaginosis go away on its own?

BV might go away on its own, but it’s usually not worth the wait.

If it does go away on its own, it may take around 2 weeks to resolve, and then keep coming back. During that time, you might experience unpleasant symptoms.

How long does BV take to go away?

After seeing a doctor and starting treatment with a prescribed medication, your symptoms will likely improve within 2–3 days.

However, it’s important to continue taking your medication for the prescribed period of time, even if your symptoms have gone away. This will help ensure that the infection has completely cleared up, which typically takes about 7 days.

Should you be treated for bacterial vaginosis if you’re pregnant?

If you’re pregnant, it’s wise to get treatment for BV as soon as possible. That’s because BV can increase the risk of early delivery and other complications.

It’s safe to take antibiotics for BV while you’re pregnant. A vaginal suppository antibiotic is typically prescribed to avoid side effects like nausea, vomiting, metallic taste, heartburn, and others.

What is the difference between a yeast infection and bacterial vaginosis?

BV and vaginal yeast infections have similar symptoms but different causes and treatments. Both cause inflammation of the vagina, also known as vaginitis. Both can also cause itchiness, but yeast infections do this more.

One of the differences between BV and a yeast infection is that BV produces a foul-smelling, “fishy” odor, while a yeast infection produces a slight “yeasty” aroma to no vaginal odor at all.

Additionally, a yeast infection may cause redness and inflammation of the vulva, and white, “cottage-cheese-like” discharge, while BV doesn’t produce such symptoms.

To determine whether a vaginal infection is BV or a yeast infection, a doctor may:

  • ask about your medical history, including previous vaginal infections
  • perform an exam to look for signs of infection and vaginal discharge
  • take a sample of the discharge for analysis, to see whether an overgrowth of harmful bacteria or fungi is present
  • test the pH of the vagina; according to a research from 2018, a pH of 4.5 or above can be an indication of BV

Can I really treat BV with alternative home remedies?

If you can’t use or access antibiotics, certain home remedies — namely probiotics, garlic, and boric acid suppositories — could treat BV. However, some studies indicate that these home remedies aren’t as effective as antibiotic treatment.

The CDC reports that while some studies have evaluated supplementing Lactobacillus and other probiotics vaginally to treat BV, research does not support this to replace or add to standard BV therapy.

A 2018 study suggests other potential alternatives to antibiotic treatment, though these need to be done under a healthcare professional’s care:

A 2023 study points to the development of antimicrobial resistance worldwide and calls for development of new alternative non-antimicrobial therapies for BV.

Although mild cases of BV may resolve on their own, treatment can help lower the risk of complications. The most effective options are prescription antibiotics. These include metronidazole and clindamycin, which you may take as a pill or cream.

In some cases, a doctor might prescribe tinidazole or secnidazole. These medications are also antibiotics. Taking probiotics, garlic capsules, and boric acid may also help.

Though your symptoms might improve within a few days, be sure to take all your medication as directed. This will help make sure that your infection has completely resolved. If you have recurring BV, you can work with a doctor to find long-term solutions.