Group B Strep Testing

Why test for Group B Streptococcus?

Without preventative medicine, around 700 babies born in the UK each year develop a GBS infection, making it the most common cause of life threatening infection for new born babies. Most GBS infection in new born babies can be prevented by giving high risk mothers intravenous antibiotics from the onset of labour until the baby is born. If the mother is a carrier and is not treated during delivery, the risk of her baby developing a GBS infection is 1 in 300, if treated during labour this is reduced to less than 1 in 6000.

Kingsbridge Private Hospital offer GBS testing with TDL laboratories who use an Enriched Culture Medium (ECM) specifically designed to isolate GBS in swabs. Pregnant women should be tested for GBS between 35 and 37 weeks gestation, which allows enough time to get results and is also close enough to the delivery date to minimise the risk of GBS infection during labour. The test can be carried out at our clinic or as a home test. 

Please note that the test is not 100% sensitive and thus there can be false negatives (I.e. there is a chance that you could have a negative result when you are in fact positive). There is also a small chance that you could acquire the infection between testing and giving birth; this is minimised but not eradicated by testing late in pregnancy at 35-37 weeks gestation.