What is Bacterial Vaginosis?
Bacterial vaginosis (BV) is the most common form of vaginal infection yet a poorly understood condition in which the balance of bacteria inside the vagina becomes disrupted. This imbalance often triggers a change to the usual vaginal discharge, which results in a fishy smelling, greyish discharge from the vagina. BV should not be confused with yeast infection (Candidiasis), or infection with Trichomonas vaginalis (Trichomoniasis) which are not caused by bacteria. Bacterial Vaginosis is not generally considered to be a sexually transmitted infection.
Around one in three women will experience at least once episode of BV at some point. Simple tests carried out by healthcare professionals can diagnose the presence of BV. However, half of women with bacterial vaginosis have no symptoms. If you do not have symptoms, there is no need to get tested as bacterial vaginosis without symptoms does not pose a threat to health or to pregnancy.
See your GP if you notice any abnormal discharge from your vagina, especially if you are pregnant. It is important to get this type of symptom diagnosed quickly to rule out other infections and prevent complications.
What are the symptoms of Bacterial Vaginosis?
The main symptom of bacterial vaginosis (BV) is a change in your usual vaginal discharge.
Your discharge may:
become thin and watery
change to a white or grey colour
develop a strong, unpleasant, fishy smell, particularly after sexual intercourse
Some women also complain of vaginal discomfort due the increased vaginal discharge and slight pain during intercourse or when passing urine. BV is often mistaken for Thrush, as symptoms are similar and there is a greater awareness of Thrush although it is a much less common condition,
Around half of all women with BV do not have any symptoms, however BV may be diagnosed when vaginal swabs are taken for other reasons. If you do not have symptoms, there is no need to get tested to find out if you have BV as asymptomatic bacterial vaginosis does not pose a threat to health or pregnancy.
What causes bacterial vaginosis?
The cause of bacterial vaginosis – sometimes called BV - is not really understood. In women who have bacterial vaginosis you find:
Less of the normal vaginal bacteria (lactobacilli)
An overgrowth of other types of bacteria in the vagina
A change in pH (acid/alkaline balance) of the vagina with the vagina becoming more alkaline.
How do you get Bacterial Vaginosis?
Bacterial vaginosis can occur if you:
Use scented soaps or perfumed bubble bath
Put antiseptic liquids in the bath
Douche or use vaginal deodorant
Use strong detergents to wash your underwear
Hormonal changes during the menstrual cycle, semen in the vagina after sex without a condom, an intrauterine contraceptive device and genetic factors may also play a part.
Bacterial vaginosis is not a sexually transmitted infection, but women who are sexually active and have had a change of partner are more likely to have it, including women in same sex relationships.
What are the signs and symptoms of bacterial vaginosis?
Around half of women with bacterial vaginosis will not have any signs or symptoms at all, or may not be aware of them. If you get symptoms you might notice change in your usual vaginal discharge. This may increase, become thin and watery, change to a white/grey colour and develop a strong, unpleasant, fishy smell, especially after sexual intercourse. Bacterial vaginosis is not usually associated with soreness, itching or irritation.
Is bacterial vaginosis an STI?
It is unclear whether BV is a sexually transmitted infection (STI) as there is conflicting evidence on this issue.
Evidence that suggests BV could be an STI includes
rates of BV are higher in women who have multiple sexual partners
rates of BV are lower in women who use a condom during sex
There is also evidence that women with BV can pass the condition to women they have sex with, although exactly how this happens is still unclear.
Evidence that suggests BV may not be an STI includes:
treating male partners with antibiotics does not prevent the reoccurrence of BV
rates of BV can vary significantly in different ethnic groups, which cannot be explained by sexual activity alone
BV can occur in women who are not sexually active
Many experts think that sexual activity plays a role in BV, but other factors are probably also responsible for the condition.
It may also be possible that an initial episode of BV is caused by some type of sexual infection, but further episodes are caused by other factors.
How will I know if I have bacterial vaginosis?
If you think you may have it talk to a doctors or nurse who might recommend a test if you have the signs and symptoms. You may notice these yourself or they may be noticed by a doctor or nurse during a vaginal examination.
Some women may also be offered a test during pregnancy and before some gynaecological procedures or an abortion.
Bacterial Vaginosis is not a sexually transmitted infection but it is important that you’d delay getting advice if you think you may have been at risk of a sexually transmitted infection.
What does the test involve?
A doctor or nurse will look at any vaginal discharge and use a swab or a small plastic loop to collect a sample of cells from the walls of the vagina, during an internal examination. A swab looks a bit like a cotton bud, but is smaller, soft and rounded.
The swab or loop is wiped over the parts of the body that could be affected and easily picks up samples of discharge and cells. It only takes a few seconds and is not usually painful, though it may be uncomfortable for a moment.
The pH (alkaline/acid balance) of the vagina may be measured by wiping a sample of vaginal discharge over a piece of specially treated paper. Samples taken during the examination are looked at under a microscope to check for bacterial vaginosis. In some services, the result is available immediately. In other a sample is sent to a laboratory, and the result is usually available within a week.
Sometimes bacterial vaginosis is noticed during a cervical screening test, but you will only need treatment if you have problems with discharge. Routine blood tests do not detect infections such as bacterial vaginosis.
How accurate are the tests?
Tests for bacterial vaginosis are usually accurate. The doctor or nurse will discuss your test results with you.
Do I need to have a test to check that the bacterial vaginosis has gone?
You only need another test if:
Signs and symptoms don’t go away
Signs and symptoms come back
You are treated for bacterial vaginosis in pregnancy
What happens if bacterial vaginosis isn’t treated?
For many women bacterial vaginosis goes away by itself. However, there is some research to suggest that women with bacterial vaginosis may be at a higher risk of having pelvic inflammatory disease (PID) or getting HIV.
Does my partner need treatment?
Men don’t get bacterial vaginosis so male partners do not need treatment. Female partner should get advice from a doctor or nurse about whether they need treatment.
Will bacterial vaginosis affect my chances of getting pregnant?
There is no evidence that bacterial vaginosis will affect your chances of getting pregnant.
What happens if get bacterial vaginosis when I’m pregnant?
Bacterial vaginosis may cause problems with a pregnancy. The infection has been found in some women would have has a miscarriage, a premature birth or a low birth weight baby.
Bacterial vaginosis can safely be treated when you are pregnant and when you are breastfeeding – this won’t harm the baby, but do tell the doctor or nurse that you are pregnant. This will influence the type of treatment that you are given.
Pregnant women who have has a previous premature birth will usually be offered a test for bacterial vaginosis.
Does bacterial vaginosis cause cervical cancer?
There is no evidence that bacterial vaginosis cause cervical cancer.