Group B Streptococcus Infection
An infection of concern to midwives, obstetricians and paediatricians is called Group B Streptococcus or’ Group B Strep’. Group B Strep is a bacterium found in your vagina and gut which is present in up to a third of the population and it is transient, meaning it may not always be present throughout your pregnancy. We all have colonies of different bacteria in our digestive tracts, throats, skin, etcetera, and most of the time they do not make us ill.
Confusion exists around Group B Strep with many couples anxious about the safest course of action. Currently in the U.K. women are not routinely screened for this infection because it is transient although women will be offered a test for the infection if they present with a vaginal discharge or threatened premature labour. The swabs take 48 hours to grow the bacteria and if the Group B Strep is identified then antibiotics are offered in labour to protection the baby. Use of antibiotics is not risk free, and the greatest risk is that you become sensitive or allergic to them and they can also cause nausea and diarrhoea.
Around 50 percent of babies born to mothers carrying Group B Strep will pick up the bacteria and be colonised by it. About one to two percent of that group will go on to develop severe Group B Strep infection, either as early onset (before two days old) or late onset (after two days old). Even with medical care ten percent of those babies that develop a severe infection will die. This severe infection or ‘sepsis’ is most likely to occur in babies who are premature and where there has been prolonged rupture of membranes, usually longer than 24 hours.
With sepsis being a real danger to new born babies you may wonder why every woman is not given antibiotics, regardless of whether the swab is positive or negative. In the USA screening for and treatment of Group B Strep is routine and they greatly reduced their Group B Strep infection rate in newborns. However, the number of babies dying of infections remained constant because other infectious bacteria took hold. Antibiotics merely removed one bacterium leaving a vacuum for another.
Current NICE guidance is to limit antibiotic use and hospitals have differing guidelines on the management of Group B Strep however routine screening of all women for Group B Strep is not recommended, only those that are in a risk group.
NICE recommend intravenous antibiotic cover continuously throughout labour if you have had a positive Group B Strep swab result in this pregnancy or have previously had a baby infected with Group B Strep. If you wish to be tested for Group B Strep and do not fall into a risk group you can get it done privately through your family doctor. Or there is a postal service which can be found on the Group B Strep Support website. The test should ideally be carried out between 35-37 weeks of pregnancy.
If you do test positive for Group B Strep the antibiotic of choice is benzylpenicillin and there is an alternative for those allergic to penicillin. Both are given through a needle in your hand every four hours during labour and providing you’ve had at least two doses of the antibiotic during your labour paediatricians will usually monitor your baby for signs of infection over a few days. If you gave birth before getting two doses paediatricians may advise that baby has intravenous antibiotics. The antibiotics are very effective at combatting Group B Strep and the risk of your baby developing this infection drops from one in three hundred to less than one in six thousand.