Is my unborn baby at risk of early-onset GBS (group B streptococcus) infection?

Early-onset GBS (group B streptococcus) infection is rare. Of the approximately 700,000 babies born in the UK every year, GBS causes infection in at least 700 babies if no preventative action (such as antibiotics given through a vein) is taken.

What is early-onset GBS?

GBS stands for group B streptococcus. It is one of many bacteria that can be present in our bodies. It usually causes no harm.

About 25% of women carry the bacteria in their vagina. This means that many babies come into contact with the bacteria during labour or birth. GBS causes no harm to most babies, but a small number of babies may become seriously ill if they are infected.

In early-onset GBS, symptoms of the infection begin in the first week of life, and usually within the first 12 hours.

What increases the risk of early-onset GBS?

There may be a higher risk of your baby developing a GBS infection if:

  • you have previously had a baby with a GBS infection
  • GBS is found in your urine during tests that were carried out for other purposes – for example, to check if your bladder and kidneys were functioning normally
  • GBS is found during vaginal and rectal swabs that were carried out for other purposes – for example, to check if you had an infection inside your vagina
  • you have a high temperature during labour
  • you go into labour prematurely (before 37 weeks of pregnancy)
  • you give birth more than 18 hours after your waters have broken

As a precaution, mothers of high-risk babies can be given antibiotics during labour. These will be given through a vein (intravenously).

In the UK, pregnant women are not routinely screened for GBS.

Find out more about treatment for GBS.

What are the symptoms of early-onset GBS?

Symptoms of an early-onset GBS infection include:

  • being floppy and unresponsive
  • poor feeding 
  • grunting when breathing
  • irritability
  • an unusually high or low temperature
  • unusually fast or slow breathing
  • an unusually fast or slow heart rate

Find out more about the symptoms of GBS.

Babies who have symptoms of an early-onset GBS infection should be treated with antibiotics as soon as possible.

Read the answers to more questions about pregnancy.

Further information:

Page last reviewed: 28/04/2014

Next review due: 27/04/2016