Group B Strep testing - should I get tested?

Posted 10 July 2018 in Womens health

Group B Strep - should I get tested?

Group B Strep is the most common cause of life-threatening infection in newborn babies in the UK, and the most common cause of meningitis in babies under age 3 months and yet a lot of pregnant mums know nothing about it!Pregnant Lady holding a flower Group B Strep Blog

At least two babies every day in the UK fall ill with Group B Streptococcus (often known as Group B Strep or just GBS). For some, the illness is fatal, for others, it can cause permanent disabilities.

The following information may help you to gain a better understanding of GBS and to make an informed decision on whether a GBS test may be right for you! (1)

What is GBS?

GBS is a type of bacteria which forms part of the natural bodily flora of up to four in ten people. Up to a quarter of women also carry the bacteria in the vagina. Usually, the bacteria are harmless, but in certain cases such as in people with a compromised immune system, babies and pregnant women, it may develop into an infection. (1)

If a woman carries GBS in her vagina and becomes pregnant, there’s a small chance that she could pass the bacteria on to the baby during childbirth. Because the immune system of babies is not yet developed, it is much easier for GBS to get out of control and make them ill. For a small number of babies it can be life-threatening, causing blood poisoning, pneumonia and meningitis. This may lead to death in a very small number of cases. (2)

Will the NHS test for Group B strep?

Despite this, there is no routine testing provided on the NHS. Even if a pregnant woman is offered testing it’s usually the Standard ‘non-selective’ test for group B Strep carriage. A negative result using this method is not very reliable – it gives a high proportion of falsely negative results. 

However, there is another test that can be obtained from Webmed Pharmacy and this is the GBS-specific ECM(Enriched Culture Medium), which is the international ‘gold standard’ for detecting GBS. These tests are highly reliable and are good predictors of your GBS carriage status for 5 weeks after the swabs have been taken.  

Therefore, it’s best to test in the 5 weeks before you go into labour and give birth. The 35-37 week ‘window’ for testing is usually thought to be the best time to test for most people as your GBS carriage status is not likely to change between testing and giving birth, and you should receive the result before your baby arrives.

What are the symptoms of GBS?

If GBS infection is going to occur, it usually does within the first few hours of birth, but it may occur as late as when the baby is aged three months. Symptoms include:

  • the baby becoming limp and floppy

  • lack of response to stimuli

  • a grunting noise when breathing

  • high or low temperature

  • rapid or slow breaths

  • rapid or slow heartbeat

The appearance of any of these symptoms warrants a 999 call or an immediate visit to A&E. Time is of the essence as once the infection has taken hold, the difference between life and death can be a matter of hours. If the baby is diagnosed with GBS, they will be treated in hospital with antibiotics administered via a vein. (2)

How does GBS testing work?

If you’re pregnant and concerned about your baby contracting GBS, you can  consult your midwife or GP to help you decide whether to get tested. (2)

At Webmed Pharmacy, our testing kit allows you to take both a vaginal swab and a rectal swab to send off for testing (the above link takes you to the product specific page which explains the test in detail). If your results come back positive, you need to tell your midwife or GP. Your birth plan will need to be reconsidered if you’ve intended not to give birth in hospital. (2)

When you go into labour or your waters break, let your midwife know immediately. You will need regular injections of antibiotics into a vein throughout the labour. Any allergies to antibiotics must be reported to your midwife so they can ensure hospital staff administer a safe antibiotic for you. The hospital may want to keep a close eye on the newborn baby in case any signs of GBS infection arise, so you may need to stay in hospital for up to twelve hours after the birth as a precaution. If symptoms do appear, the baby will be given urgent antibiotics into a vein. (2)

For further information, visit the Group B Strep Support website.

Why take the risk - test now!

Click here to buy your Group B Strep test.

Author: Gabby Gallagher MPharm

Medically reviewed by: Superintendent Pharmacist Margaret Hudson BSc(Hons)MRPharmS 10/07/18


  1. Group B Strep Support. What is group B Strep? [cited 6 July 2018]. Available at:

  2. NHS Choices. What is group B strep? [cited 6 July 2018]. Available at:

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