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Understanding bacterial vaginosis and BV testing

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Bacterial vaginosis (BV) is a common condition that affects the vagina, causing a change in the smell and consistency of discharge. Although BV is harmless in itself, the symptoms can be unpleasant. It can also make you more vulnerable to certain STIs, which is why it’s a good idea to seek treatment if you think you have it.

Causes of bacterial vaginosis

Bacterial vaginosis is caused by a disruption to the bacteria that naturally occur in the vagina. A normal healthy vagina is home to millions of different bacteria, which exist in a delicate balance and keep the environment of the vagina slightly acidic.

With bacterial vaginosis, this balance is thrown off, and “bad” bacteria begin to increase, which causes a decrease in “good” bacteria (lactobacilli). This makes the vagina slightly less acidic and more alkaline, which in turn leads to the growth of more “bad” bacteria and fewer lactobacilli.

While we don’t fully understand why this change happens in the first place, we know there are some lifestyle habits that can make BV more likely, including:

  • Being sexually active
  • Changing sexual partners
  • Having an IUD (coil)
  • Washing your vagina with perfumed products
  • Being a smoker

There’s a misconception that because bacterial vaginosis causes smelly discharge, it’s a symptom of being unhygienic. In fact, as we’ve noted above, you’re more likely to develop BV if you wash your genitals excessively, particularly if you use strong soaps or deodorants.

Symptoms of bacterial vaginosis

The characteristic symptom of bacterial vaginosis is a change to your vaginal discharge. Healthy vaginal discharge is usually white or clear in colour, and thick and sticky or slippery and wet. It shouldn’t have a strong or unpleasant smell.

By contrast, BV discharge can be:

  • Very smelly with a strong fishy odour – this might be particularly noticeable after sex
  • Grey-white in colour
  • Thin and watery

You shouldn’t have any itching or soreness with BV, so if you are the cause may something else like thrush or a sexually transmitted infection.

Testing for bacterial vaginosis

If you think you have bacterial vaginosis, it’s a good idea to go to a sexual health clinic or see your GP. To confirm BV, your doctor or nurse will normally need to speak to you about your symptoms and take a look at your vagina. They also might need to take a swab so they can test for BV and other infections that cause similar symptoms.

If you’d rather not have an appointment in person, there are home test kits available, including the Canetest Self-Test for Vaginal Infections. A positive result for BV using one of these tests means you can speak to your pharmacy or GP about treatment options.

Treatment for bacterial vaginosis

The standard prescription treatment for bacterial vaginosis is a course of antibiotics. These are given as tablets, or as a cream or gel. You’ll usually need antibiotics for five to seven days, but a longer course may be appropriate if you keep getting BV.

There are some alternative treatment options for BV that are available without a prescription, but they may not be as effective as antibiotics. Products like Balance Activ and Canesbalance contain lactic acid, which encourages lactobacilli to grow and restore the acidic environment of the vagina.

In addition to using treatments, it’s a good idea to do the following to help your symptoms clear and prevent a recurrence of BV:

  • Have showers instead of baths
  • Wash your genitals with water and plain soap
  • Avoid strong, perfumed soaps and bubble baths
  • Avoid vaginal deodorants and douches
  • Avoid washing your underwear with strong detergents
  • Try to quit smoking

Bacterial vaginosis in pregnancy

If you’re pregnant, you should speak to your GP or midwife if you notice a change if your vaginal discharge. For some pregnant women, BV can cause complications so it’s a good idea to get checked and treated as soon as possible.