Information if you’re not pregnant

GBS colonisation

GBS is a normal bacterium which is carried by 20-40% of UK adults, most commonly in the gut, and for up to 25% of women, in the vagina, usually without symptoms or side-effects.  Carrying group B Streptococcus (GBS) is perfectly normal and natural whether you are pregnant or not.  Carrying GBS does not need treatment. GBS is not a sexually transmitted disease; indeed, carrying GBS is not a disease at all.

A positive rectal or vaginal swab result for GBS means the person is carries GBS at the time the samples were taken – not that they are ill. (However, GBS found in the urine usually means a GBS infection is present and should be treated at diagnosis with oral antibiotics and the treatment repeated until urine tests come back clear.) 

Vaginal symptoms

We know of no publication that convincingly demonstrates that GBS carriage causes vaginal symptoms.

Carrying GBS is asymptomatic – it is not associated with any symptoms. To establish whether you are carrying GBS, you need to test and, to do this, the sensitive ECM test is the ‘gold standard’ test.

It should be remembered that, even if GBS is grown from a swab sample taken from the vagina,  this only means that the vagina was colonised with GBS when the swab was taken – it does not mean that GBS is the cause of those symptoms.

GBS can occasionally cause infection in adults.  For more information, please click here.