Bacterial vaginosis (BV)

A fishy smell and a thinner, greyish-white discharge can be signs of bacterial vaginosis (BV). Some people notice the smell more after sex. Many people with BV have no symptoms at all.

BV is when the balance of bacteria in the vagina changes. The NHS doesn’t class it as an STI (sexually transmitted infection), though sex can trigger it or pass it on. People who have never had sex can get BV too.

What symptoms can and cannot tell you

The NHS says BV doesn’t usually cause soreness or itching. Mention either at your appointment, but neither can tell you the cause on its own. A clinician may need to check for BV and other infections, including STIs.

Describe the change in your own words. Say how it smells, whether the discharge is thinner than before, and any discomfort. If you’ve already tried a vaginal product, bring its name. You can ask what the examination or sample is meant to check.

Why the bacterial balance changes

No one fully knows what causes BV. Douching and sex with a new partner or more than one partner are linked with it. They may play a part, but they can’t explain why a particular bout happened.

You can’t catch BV from toilet seats, bedding or swimming pools. Cleaning inside the vagina doesn’t help either. WHO names washing or douching inside the vagina as risk factors, along with putting herbs or other products inside.

Avoid vaginal deodorants, washes and douches, and keep perfumed products out of your bath. These are among the NHS tips for easing symptoms and stopping BV coming back. Don’t wash inside the vagina, even if the smell is stronger.

Checking and treating an episode

A GP, doctor or sexual health clinician will ask about your symptoms and may examine your vagina. They may take a sample of discharge with a cotton swab to check for BV and other infections. A change in your discharge is a good reason to get checked.

Treatment is usually prescribed antibiotics, as tablets or a gel or cream for the vagina. Your clinician can advise which suits you. Follow the instructions even if the discharge or smell settles. Ask your pharmacist or doctor about anything that isn’t clear.

BV often comes back after treatment. A GP or sexual health clinic can talk about another treatment plan and possible triggers, such as sex or periods. Bring the dates of past bouts and the names of treatments you’ve tried.

When a partner may need treatment

This advice changed recently. ACOG’s newer US guidance advises thinking about treating male sexual partners at the same time, for adults whose BV keeps coming back with symptoms.

Published advice differs. CDC’s older public information still says male partners don’t need treatment. NHS information says a partner who is a woman or has a vagina may also need treatment. Ask your clinician how the newer evidence applies to you, especially if your symptoms keep coming back.

You could ask: “Would it help to treat my partner?”, “What are the benefits and what’s still uncertain?” and “What follow-up do we each need?” Ask the clinician to plan treatment for each of you. Don’t try to share or combine separate prescriptions.

Pregnancy and getting help

If your vaginal discharge changes during pregnancy, contact your GP or midwife in the UK, or your doctor or midwife in the US and elsewhere. BV is linked with problems in pregnancy, including premature birth. But the NHS says it causes no problems in most pregnancies.

Go to A&E now (UK), or an emergency department (US and elsewhere), for pain in your pelvis that is severe or getting worse, or comes with feeling faint or heavy vaginal bleeding.

Contact an urgent GP service or NHS 111 today (UK), or your doctor or urgent care service (US and elsewhere), if changes in discharge come with pain in your pelvis or low in your tummy.

If you’re not pregnant and think you have BV, or it comes back, book a GP or sexual health appointment in the UK, or a doctor or sexual health appointment elsewhere. BV is also linked with a higher risk of getting other STIs, so ask whether testing would help.