Like many other bacteria, Group B Streptococcus (GBS) lives in our bodies and usually causes no harm.
This is called GBS carriage, colonisation with GBS or carrying GBS.
It is estimated that a quarter of pregnant women in the UK carry GBS in their vagina and rectum. As a result, when a baby is born they come into contact with the bacteria. Usually no harm is caused to the baby, but in a small number of cases the baby can become seriously ill with GBS infection.
Early-onset GBS infection is when the infection occurs in the first week of a babys life. In rare cases the baby can develop the infection up to the first three months of its life in which case it is called late-onset GBS infection and is usually unassociated with the pregnancy.
Early-onset GBS InfectionApproximately 1 in every 1,600 babies born in the UK and Ireland develops early-onset GBS infection. On average around 440 babies are affected each year.
GBS infections can cause life threatening illnesses such as septicaemia (blood poisoning), pneumonia (infection of the lungs) or meningitis (infection of the lining of the brain). Early-onset GBS is fatal to one in ten of the babies diagnosed.
However, early-onset GBS can be prevented if pregnancies at increased risk of the infection are identified and appropriately managed.
Managing Pregnancies at Increased RiskIntravenous antibiotics throughout labour are highly effective at reducing the risk of passing on GBS infection to the baby. This treatment reduces the risk of a baby developing early-onset GBS infection by about 90%.
Guidelines to Prevent Early-Onset GBS If you have previously had a baby who had GBS infection when it was born you should be offered antibiotics during labour. If you carried GBS during a previous pregnancy but your baby did not develop a GBS infection, treatment during labour is not recommended.
If you have had swabs from your vagina or rectum and GBS has been identified you should discuss with your doctor the possibility of antibiotic treatment during labour. Treatment before labour does not reduce your chance of carrying GBS at the time of the birth.
If GBS is present in your urine you should discuss with your doctor the possibility of antibiotic treatment during labour.
Reasons your baby may be at high risk of developing GBS infection includeYour temperature is higher than 38C (100.4F) during labour
You go into preterm labour (before 37 weeks of pregnancy)
Your waters have broken prematurely
Your waters have broken for more than 18 hours. In this case you should discuss with your doctor the possibility of antibiotic treatment during labour.
Penicillin is usually the antibiotic given during labour to reduce the risk of early-onset GBS infection. For those who are allergic to penicillin, clindamycin is used as an alternative.
Antibiotic treatment is not recommended if you plan to have a Caesarean section.
Screening and Testing for GBS in PregnancyScreening for GBS carriage during pregnancy is not routinely recommended in the UK. The main reason for this is that given the relatively low risk associated with most cases of GBS carriage, a positive test may result in unnecessary and potentially harmful treatment.
In some circumstances there is a need to find out if you carry GBS. If you are offered a test to detect GBS carriage it is important that you understand the purpose of the test and are clear about the implications of having a positive and negative result.
The most sensitive testing method requires swabs to be taken from both your vagina and rectum, which are then processed in a laboratory in a special solution. This process is not widely available within the NHS but it is available privately.
GBS carriage can come and go, but if you have a test done a few weeks before delivery is considered relatively reliable at predicting whether or not you will carry GBS around the time of the birth.
When no other risk factors are present, about 1 in every 500 babies born to mothers with a positive test is likely to develop early-onset GBS infection. Even if you have a negative test result, it is not guaranteed that you will not be a carrier of GBS around the time of delivery.
After the BirthThe majority of babies born to mothers who carry GBS are born healthy. If a baby is thought to have a GBS infection, samples of blood or fluid from the spinal cord can be tested. Most babies with GBS infection can be treated with intravenous antibiotics and make a full recovery. Healthy babies will not need to be tested for GBS infection.
May 2011 | 
Pregnancy And Contact Lenses
