It’s important to remember that group B Streptococcus (GBS) is a natural and normal bacterium that colonises 20-30% of all adults (men and women) without symptoms or side-effects. It is usually found in the intestines as part of your normal gut flora. It can also found in the vagina living as a ‘commensal’ – an organism which lives in or on another without causing any harm. It is not a sexually transmitted disease and simply carrying GBS does not require treatment of the woman or of her partner. While this bacterium is normal and natural and does not require treatment on its own, in pregnancy it deserves more notice.

There is a risk, if Mum is a carrier, of passing it on around labour, potentially leading to group B Strep infection in her baby. Group B Strep is the most common cause of life-threatening infection in newborn babies and of meningitis in babies up to three months. At least 500 babies a year in the UK become infected. One in 10 sick babies die, one in 20 survivors suffer long term problems, and five in 10 survivors of group B Strep meningitis suffer long-term mental and physical problems including cerebral palsy.

Prevention is better than cure.

Even though routine antenatal screening for group B Strep is not recommended by the UK National Screening Committee nor the Royal College of Gynaecologists and Obstetricians, this does not mean that you can’t still ask to be tested. The two most common tests are the conventional NHS test and the ECM test. The ECM test is considered the ‘gold standard’ for detecting group B Strep carriage. The conventional NHS test will miss up to half of the women carrying GBS when the swabs are taken. If your NHS Trust does not provide ECM testing, you can order an at-home test pack from private labs for around £35.

35 to 37 weeks of pregnancy is suggested for testing, as the result of an ECM test done then has shown to be a highly predictive indicator of whether you will be carrying for the next five weeks when you’re most likely to go into labour. Please feel free to call us on 01444 416176 or visit our website ( for more information on where you can get the ECM test. UK guidelines recommend that, if you have had any positive GBS test result (from the vagina, rectum or urine) during your current pregnancy, you should be offered intravenous antibiotics from the onset of labour and then at intervals until delivery.

Luckily, the contribution of group B Strep to prenatal infection is fairly small. We would be remiss however if we didn’t point out that group B Strep is one of a number of bacteria found in the vagina that can cause infection in a baby while still in the womb, which can result in late miscarriage, stillbirth or a baby born very poorly indeed. However, thankfully these complications are not common and are usually caused by a variety of factors other than group B Strep, for example, genetic defects, gynaecological problems, other infections, etc.

Knowledge is power, and the more parents-to-be can educate themselves the more empowered they feel. As we’ve covered above, just because group B Strep testing is not routine practice does not mean you can’t still ask for an ECM test or order one privately. If you test positive in your current pregnancy then UK guidelines state you automatically should be offered the option of antibiotics during labour. Also, tracking your cheeky little darling’s movements and learning their definition of ‘normal’ will also empower you as a mum before they even arrive…safely and healthily!

For any further questions or concerns, please contact: