Bacterial vaginosis (BV) results from an imbalance in numbers of beneficial and harmful bacteria in the vagina. It can cause vaginal itchiness, unusual discharge, and a characteristic odor, among other symptoms.

The body may be able to clear BV on its own, but without treatment, the condition can increase the risk of other health issues. For this reason and because the symptoms can be uncomfortable, anyone with BV symptoms should consult a healthcare professional.

This article describes what BV feels like, as well as its causes, possible complications, and home remedies and treatments. It also looks at how to prevent BV, and how to distinguish BV from a yeast infection.

BV is the most common vaginal condition among females of childbearing age.

About 50–75% of females with BV have no symptoms. If these occur, they typically involve changes to vaginal discharge, such as an increased amount. There may also be a burning sensation or itchiness in the vaginal area.

In someone with BV, vaginal discharge may have:

  • a watery, thin consistency
  • a gray or white color
  • a strong, unpleasant smell, often described as fishy

A person may also have a burning sensation during urination and itching around the outside of the vagina, though this is less common.

BV itself is not harmful, but it can increase the risk of other health issues.

General health complications

Pregnancy complications

Possible complications of BV during pregnancy include:

Chorioamnionitis significantly increases the chance of an early delivery. If the newborn lives, they have a higher risk of cerebral palsy.

Fertility complications

BV may directly increase the likelihood of difficulty conceiving. And it may increase the risk of health complications that can affect fertility.

Possible complications include:

  • Tubal factor infertility: This is infertility caused by damage to the fallopian tubes, which connect the ovaries to the uterus.
  • Pelvic inflammatory disease: This involves an infection and inflammation of the upper female genital tract, and it can have serious effects, including infertility.
  • Unsuccessful in vitro fertilization (IVF): If a person has BV, any IVF treatments may be less likely to succeed.

BV results from an imbalance in the populations of beneficial and harmful bacteria that naturally live in the vagina.

An imbalance can occur for many reasons, including:

BV often develops after sex with a new partner. BV is not an STI, but it can increase the risk of developing an STI.

The role of bacteria

All parts of the body have bacteria, and only some are harmful. Health problems can arise when there are more harmful bacteria than helpful bacteria in a given area.

Most bacteria in the vagina are helpful, and BV occurs when the harmful bacteria grow in number.

The vagina should contain bacteria called Lactobacilli. They produce lactic acid, making the vagina slightly acidic. This prevents some harmful bacteria from growing there.

Having lower levels of Lactobacilli can cause the vagina to become less acidic. If the vagina is not acidic enough, harmful bacteria can grow and thrive.

Experts still do not understand exactly how these harmful bacteria are linked with BV.

Risk factors

Anyone with a vagina can develop BV. These factors can increase the likelihood of having it:

  • using certain feminine hygiene products, such as vaginal deodorants and douches
  • using a perfumed bubble bath
  • using some scented soaps
  • bathing in water that contains antiseptic liquids
  • washing underwear with a strong detergent
  • having sex with a new partner
  • having multiple sex partners
  • smoking

A person cannot acquire BV from:

  • toilet seats
  • bedding
  • swimming pools

One home remedy that may help treat BV is probiotics. These are live bacteria that are beneficial. The term “probiotics” also describes some beneficial yeasts.

As a 2021 review notes, multiple studies have demonstrated that probiotics may help treat and prevent BV.

Certain probiotics can increase the number of vaginal Lactobacilli, helping to restore the natural balance of bacteria in the vagina.

These probiotics include:

  • oral Lactobacillus acidophilus
  • intravaginal L. acidophilus
  • intravaginal L. rhamnosus GR-1
  • intravaginal L. fermentum RC-14

Still, determining the most effective dosages, treatment durations, and routes of administration requires more research.

Because untreated BV can cause serious complications, anyone who has symptoms should see a healthcare professional for standard treatment. A person can also ask for information about taking a probiotic.

BV sometimes clears up without treatment. However, the symptoms can resemble those of other health issues, such as gonorrhea or trichomaniasis. And untreated BV can lead to complications, especially during pregnancy.

For these reasons, getting a professional diagnosis is key to ensure that the treatment is successful.

BV may also increase the risk of complications following a hysterectomy or some types of abortion. Some doctors recommend giving BV treatment to everyone who has these procedures, regardless of whether they have BV symptoms.

Male partners do not usually require treatment. However, BV can transmit from a male to multiple female sexual partners.

Below, we explore some treatment options for BV.

Antibiotic medication

Antibiotics are effective in up to 90% of BV cases, but the condition often comes back again within a few weeks.

Below are some antibiotic medications that a doctor may prescribe for BV.

Metronidazole

Metronidazole is the most common antibiotic treatment for BV.

It is available in these forms:

  • Oral tablets: People typically take these twice daily for 7 days. Doctors consider tablets the most effective treatment, especially if the person is breastfeeding or pregnant.
  • Single dose: The Food and Drug Administration (FDA) approved Solosec (secnidazole) in 2017 for the treatment of BV. This is the only single-dose oral BV treatment. A person sprinkles a 2-gram (g) packet onto food.
  • Gel: A person applies this gel into their vagina once a day for 5 days.

Metronidazole interacts harmfully with alcohol. This combination can make a person seriously unwell and cause side effects such as nausea and vomiting.

Clindamycin

Clindamycin is an alternative antibiotic. It may work if metronidazole is not effective or if the infection recurs.

Clindamycin cream is the first-line treatment that a person applies inside their vagina. A person does this at bedtime for 7 days.

Instead, doctors may prescribe clindamycin tablets, which a person takes twice a day for 7 days, or clindamycin ovules, which a person inserts into their vagina at bedtime for 3 days.

Clindamycin ovules and cream weaken latex, so barrier methods of contraception may be less effective during the treatment.

Some examples of these methods include:

The FDA has recently approved a new clindamycin gel, Xaciato, for the treatment of BV in females aged 12 years and older.

Learn more about the dosage and application of metronidazole and clindamycin here.

Tinidazole

Tinidazole is another antibiotic that can treat BV if metronidazole does not work or if the condition recurs.

A person takes a 2-g oral dose once a day for 2 days. Or, they take a 1-g dose once a day for 5 days.

Anyone using this medication should avoid alcohol and take their doses with food to minimize the risk of gastrointestinal side effects.

Treatment for recurring symptoms

Current treatments are associated with recurrence rates of more than 50% within 12 months of the treatment.

For recurrent BV, doctors may recommend an extended course of metronidazole. If this is ineffective, they may prescribe a metronidazole vaginal gel. A person either uses this every day for 10 days or two times a week for 3–6 months.

While there is no general consensus about the best approach, treating recurrent BV usually involves a longer course of treatment.

The medical term for a vaginal yeast infection is vaginal candidiasis.

BV is different from a yeast infection, which results from an overgrowth of Candida fungus. Instead, BV is a bacterial condition.

The two issues can cause similar symptoms. A yeast infection can cause:

BV causes vaginal discharge that is watery, white or gray, and fishy-smelling. A yeast infection typically causes vaginal discharge that is thick, creamy, and odorless. It may resemble cottage cheese.

Because a yeast infection is fungal and BV is bacterial, they require different treatments. For this reason, it is crucial to receive a professional diagnosis before treating the symptoms.

A healthcare professional may be able to diagnose BV from a person’s description of their symptoms and a physical examination.

During the examination, they may take a small sample of vaginal discharge and send it off for analysis. The doctor may also measure the pH balance of the vagina to check its acidity level.

If a person is sexually active and might have an STI, the doctor may order some diagnostic tests. These may involve using a swab or small plastic loop to collect sample cells from the vaginal wall.

There is no guaranteed way to prevent BV, as the exact causes remain unclear.

However, these strategies can help reduce the risk of BV:

  • using a barrier method of protection, such as a condom, during sex
  • avoiding douching
  • avoiding perfumed bubble baths
  • not using scented soaps or vaginal deodorants
  • washing underwear in gentle detergents

BV is a common condition that results from an imbalance in the numbers of helpful and harmful bacteria in the vagina.

Experts do not fully understand what causes this imbalance. But certain factors appear to increase the risk, such as using feminine hygiene products and having sex with a new partner or multiple partners.

Untreated BV can increase the risk of STIs and cause complications, some of which relate to pregnancy and fertility.
The symptoms of BV can also mimic those of other health issues that need different treatments. For these reasons, anyone with BV symptoms should contact a healthcare professional before they try a treatment or remedy.