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Group B Streptococcus and pregnancy

Group B Streptococcus (also called GBS or Strep B) is a bacterium carried by up to 30 per cent of people without causing harm or symptoms. In women it is found in the intestine and vagina and causes no problem in most pregnancies. In a very small number it infects the baby, usually just before or during labour, and can lead to serious illness.

Treatment for Strep B

In some circumstances antibiotics can reduce the risk of a baby developing Strep B. You may be offered antibiotics during labour if:

  • you have previously had a baby with Strep B infection
  • Strep B has been found in your urine in your current pregnancy
  • Strep B has been found on swabs from your vagina and/ or rectum which have been taken for another reason
  • you have a high temperature during labour
  • you go into labour prematurely (prior to 37 weeks of pregnancy)
  • your waters have broken more than 18 hours and you have not yet given birth

Your doctor or midwife will assess whether you need to be given antibiotics during labour. If you need antibiotics, they will be given through a vein (intravenously).

Screening for Strep B

In Northern Ireland, as in the rest of the UK, routine testing for Strep B in pregnancy is not currently recommended because there is insufficient evidence to support it. This position is kept under regular review.

If you are concerned about GBS, discuss it with your doctor or midwife.

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