Bacterial vaginosis is an infection in the vagina that can cause bad-smelling vaginal discharge. “Vaginal discharge” is the term doctors and nurses use to describe any fluid that comes out of the vagina (figure 1). Some amount of vaginal discharge is normal. But people with bacterial vaginosis can have a lot of vaginal discharge, or vaginal discharge that smells bad.

Bacterial vaginosis is caused by certain bacteria (germs). The vagina normally has different types of bacteria in it. But when the amounts or the types of bacteria change, an infection can happen.

Bacterial vaginosis usually affects people who are, or have been, sexually active. Your risk of getting it increases if you have a new sex partner or more than one partner. This is true whether your partners are male or female.

If you have bacterial vaginosis, you have a higher chance of catching other infections that are spread through sex. You can lower this risk by using condoms when you have sex.

Some people with bacterial vaginosis have no symptoms. When symptoms do happen, they often include a “fishy-smelling” vaginal discharge. The discharge is watery and off-white or gray. The smell might be more noticeable:

  • During your period
  • After sex with a male partner – This happens when semen (the fluid that is released during sex) mixes with your vaginal fluids.

You might also notice a burning feeling in your vagina.

Yes. Your doctor or nurse will do an exam. They will also take a sample of your vaginal discharge, and do lab tests on it to look for an infection.

Bacterial vaginosis is treated with medicine. The 2 medicines most often used are:

Both of these medicines come in different forms. They can come as a pill that you swallow or as a gel or cream that you put inside your vagina. Most people have fewer side effects when they use the gel or cream treatment. But you and your doctor or nurse will decide which medicine and which form is right for you.

It is important that you take all of the medicine your doctor or nurse prescribes, even if your symptoms go away after a few doses. Taking all of your medicine can help prevent the symptoms from coming back.

It depends. If your sex partner does not have a vagina, they do not need to be treated if you have bacterial vaginosis. But if your partner does have a vagina, you should tell them about your bacterial vaginosis. That way they can be treated.

Once you have had bacterial vaginosis, it can come back, even if you are not having sex. If your symptoms come back, let your doctor or nurse know. You might need treatment with more medicine.

Some people get bacterial vaginosis over and over again. If this happens to you, your doctor might suggest taking medicine for 3 to 6 months. This might help to prevent future infections.

If you are pregnant and have symptoms of bacterial vaginosis, tell your doctor or nurse. You might need treatment with medicine.

Sometimes. You can help prevent bacterial vaginosis by using condoms when you have sex.

You can also avoid things that increase the risk of bacterial vaginosis. For example:

  • Avoid douching (putting liquid inside your vagina to rinse it out)
  • Do not smoke, or try to quit if you already smoke
  • Avoid sharing sex toys, and clean toys between uses