GBS is found in the vagina of up to 30% of women. Normally these bacteria are harmless and most women will experience no symptoms. GBS does not generally need to be treated during pregnancy and is NOT classed as an STI. However, up to 70% of women who have GBS will pass it onto their baby during the birthing process.


While GBS doesn't affect most babies, around 1 in 250 will become unwell from infection. This usually happens within 7 days and the illness ranges from a very mild effect to severe infection including meningitis and pneumonia. GBS infection can also sometimes develop later, up to the age of 3 months.


It is recommended that all women planning a vaginal birth have a swab taken from their vagina at around 36 weeks. Usually this is easily self-collected and your Obstetrician will explain the procedure. The results are available within a week.


If you are GBS positive, it is recommended that you have intravenous antibiotics during your labour. This has been shown in studies to decrease the chances of your baby becoming sick. The usual antibiotic is penicillin however there is a good alternative if you happen to be allergic.


All newborn babies whose mothers are GBS positive are observed closely for signs of infection. If the baby is at high risk or shows any concerning signs, the Paediatrician will talk to you about antibiotic treatment.