REPROSAIT 4 U

What is Group B streptococcus?

Group B streptococcus, or GBS, also known as group B strep, is one of many different bacteria that normally live in our bodies. Approximately one third of us "carry" GBS in our intestines without knowing.

About a quarter of women also have it in their vagina (RCOG 2003:1). Most don't know it's there, as it doesn't usually cause problems or symptoms.

However, in rare cases GBS can cause serious illness and even death in newborn babies.

Although these cases are unusual, GBS is the most common cause of severe infection in newborns, particularly in the first week after birth (known as an early onset infection) (RCOG 2003:1). In the UK, about 340 babies a year develop a GBS infection.

How do I know if I carry GBS?

If you do carry GBS, you won't necessarily know as there aren't usually any ill effects. There is a test available for GBS, but this isn't done routinely in pregnancy (see Why isn't there a national screening programme for GBS? below).

Pregnant women often find out that they have GBS by chance, when they have a vaginal swab taken to check for something else. Also, GBS can come and go, so even if you've had a positive test earlier in pregnancy, you may not have GBS as you approach delivery.

It's important for pregnant women and their carers to know when babies are most likely to develop a GBS infection and what the signs of GBS infection in babies are.

Now I'm pregnant, what should I know about GBS?

Most babies exposed to GBS before or during birth suffer no ill effects. However, around one in 2000 babies in the UK develops a GBS infection (Heath et al cited by RCOG 2003:1; RCOG 2003:3). Sadly, about one in 10 of these babies die.

It isn't clear why some babies develop an infection while others don't. What is clear is that most GBS infection in newborn babies can be prevented.
Women in higher-risk situations can be given intravenous antibiotics either from the start of labour or from when their waters break (whichever comes first) until their baby is born.

Caesareans are not recommended to prevent GBS infection in babies as they don't eliminate the risk of GBS to the baby (GBSS 2007a).
Very occasionally GBS causes infection of the uterus or urinary tract in new mothers.

Is my baby at risk of developing GBS infection?

The Royal College of Obstetricians and Gynaecologists has identified a number of factors that help to predict whether your baby is more likely to develop a GBS infection (RCOG 2003:3-6).

These include, if:

1. You go into labour prematurely (before 37 weeks of pregnancy)
   
2. Your waters break 18 hours or more before you have your baby
   
3. You have a raised temperature (38 degrees C / 100 degrees F or higher) during labour
   
4. You have previously had a baby infected with GBS
   
5. You have been found to carry GBS in your vagina and/or rectum during your current pregnancy
   
6. GBS has been found in your urine during this pregnancy (this should be treated when diagnosed, but even if you have been treated, extra precautions should still be considered during labour - see How should my labour and delivery be managed?, below).

How should my labour and delivery be managed?

If you don't fall into one of the higher-risk groups, above, your baby is very unlikely to develop a GBS infection.

If you are higher-risk, research shows that having intravenous antibiotics from the start of your labour or from when your waters break until your baby is born can prevent most GBS infections in newborn babies.

Ideally, you should have intravenous antibiotics for at least two hours before your baby is born and every four hours during labour (RCOG 2003:6). There are some risks with taking antibiotics for you and your baby so your doctor will discuss your particular case with you to see whether treatment is the best option for you.

If you have two or more of the above risk factors then your doctor is much more likely to recommend treatment during labour to reduce the risk of your baby developing an infection (RCOG 2003:6).

If you are having a planned caesarean there is no need for intravenous antibiotics unless your waters have broken or labour has already started (RCOG 2007:6).
If your baby is at higher risk of developing a GBS infection, once he is born:

1. He should be examined by a paediatrician immediately
   
2. If both you and he are completely healthy, and you had full treatment with intravenous antibiotics during labour, he may be given intravenous antibiotics
   
3. If both you and he are healthy, but you have not received full treatment with intravenous antibiotics during labour, he may be started on intravenous antibiotics until he's given the all clear
   
4. If you or he shows signs of GBS infection, he should be started on intravenous antibiotics immediately
   

The best way to treat newborns at risk of GBS infection is an area that doctors are still researching, which is why in some cases your baby may or may not be given antibiotics.

What are the risks of treatment?

Most women and babies can safely be given penicillin as the antibiotic treatment for GBS without any ill-effects. However, a small number of people are allergic to penicillin and could have a severe allergic reaction (anaphylaxis), which can be fatal.

Women who are known to be allergic to penicillin can be given another antibiotic instead (RCOG 2003:6).

Other less severe side-effects of antibiotic treatment include diarrhoea and nausea. However, there are concerns that antibiotics may affect the balance of a baby's bacterial flora in the gut (RCOG 2003:1).
These adverse effects make some doctors more cautious about using antibiotics if there is not a clear need to do so, particularly for newborns. Some prefer a "watch and wait" approach for the first 12 hours after birth before starting a course of antibiotics that may not be needed (RCOG 2003:7-10).

What are the signs of GBS infection in a baby?

GBS infections in babies are usually "early-onset" (within seven days of birth), with 90 per cent occurring within 12 hours of birth (RCOG 2003:7-8).
In many cases, symptoms of GBS infection in babies can be recognised at or soon after birth (RCOG 2003:7).

Typical signs of early-onset GBS infection include:

1. Grunting
   
2. Poor feeding
   
3. Lethargy
   
4. Irritability
   
5. Low blood pressure
   
6. Abnormally high or low temperature, heart rate and/or breathing rate
   (GBSS 2007b)
   

Although more unusual, GBS infections can also develop when the baby is seven or more days old ("late-onset" GBS), usually as meningitis with septicaemia.

Some warning signs of late-onset GBS infection may include:

1. Fever
   
2. Poor feeding and/or vomiting
   
3. Drowsiness
   (GBSS 2007b)
   

Signs of meningitis in babies may include, as well as any of the signs listed above:

1. Shrill or moaning cry or whimpering
   
2. Dislike of being handled, fretful or irritable
   
3. Tense or bulging fontanelle (soft spot on head)
   
4. Floppy and listless or stiff with jerky movements
   
5. Blank, staring or trance-like expression
   
6. Being difficult to wake
   
7. Low or high breathing rate
   
8. Turns away from bright lights
   
9. Skin that is pale, blotchy or turning blue
   (GBSS 2007b; DH 2006)
   

Red or purple spots that do not fade under pressure (such as when pressed firmly with the side of a glass) are a sign of septicaemia (DH 2006).

Early diagnosis and treatment are vital in late-onset GBS infection or meningitis. If your baby shows any of the signs above, call your GP immediately.

If your GP isn't available, go straight to your nearest accident and emergency department. The risk of your baby developing GBS decreases with age; GBS infections in babies are rare after one month of age and virtually unknown after three months (GBSS 2007).

Most babies survive with treatment, but meningitis can leave some babies with long term problems - visit The Meningitis Trust for more information.

Why isn't there a national screening programme for GBS?

There are strict criteria that have to be met before a national screening programme for any disease can be introduced (UK NSC 2003). These include weighing up factors such as the accuracy of a screening test and the risks versus benefits of treatment.
In the case of GBS, experts are not convinced that a lab test screening programme would do more good than harm. Reasons for this include:

1. Current lab testing through the NHS in the UK is not reliable enough to recommend that all pregnant women be swabbed and tested during late pregnancy
   
2. There are concerns that the widespread use of antibiotics during labour could increase the risks of severe allergic reactions (anaphylaxis) and make the labour and newborn period too medicalised
   
3. The rates of bacteria resistant to antibiotics could increase
   
4. Newborns affected by antibiotics during labour may possibly be more likely to develop allergies and have poor immune systems (RCOG 2003:1-4)

I'm carrying GBS - what now?

If you have been affected by GBS in a previous pregnancy, or you are found to be carrying it in your current pregnancy, talk to your midwife or obstetrician and agree a pregnancy and birth plan that will protect your baby from the infection.

In the vast majority of cases your pregnancy can be managed so your baby is protected and born healthy and free from GBS.

Your baby is not at risk of catching GBS from breastfeeding (RCOG 2003:8) so there is no need to change your plans if you intend to breastfeed your baby.