Here are the answers to the most common Frequently Asked Questions or FAQs that we are asked about group B Strep in pregnancy and beyond.
What is group B Strep?
Group B Streptococcus (GBS or group B Strep) is a normal bacterium which is carried by 20-40% of adults, most commonly in the gut, and for around 25% of women, in the vagina, usually without symptoms or side-effects. Carrying GBS is perfectly normal and natural and is not associated with any health risks or symptoms to the carrier. GBS can be passed from one person to another through sexual activity, but it is not a sexually transmitted disease, and is also carried by people who have had no sexual contact.
Simply carrying GBS (detected from vaginal or rectal swabs) does not require treatment. However, GBS detected in the urine/ blood usually signifies a GBS infection, which may require antibiotics treatment – your doctor can advise further. More information on GBS can be found by clicking here.
It’s good to know whether you carry GBS during pregnancy – if detected during your current pregnancy, you should be offered intravenous antibiotics in labour. These massively reduce the risk of your newborn baby developing a group B Strep infection. There are no symptoms of carrying GBS, so the only way to find out whether you are is through testing.
Intravenous antibiotics, given in labour to women who carry GBS late in pregnancy, have been shown to be highly effective at reducing the risk that a newborn baby will develop early-onset GBS infection (GBS infection developing in the first 6 days of life). They do not reduce late-onset GBS infection (developing from age 7 days and typically by age 3 months). Researchers around the world are working on developing a vaccine that will one day prevent almost all GBS infection in babies, but it’s not available yet.
Which countries offer sensitive GBS tests to pregnant women?
Countries which we understand offer sensitive tests for GBS to pregnant women: Australia, Argentina, Bangladesh, Belgium, Brazil, Bulgaria, Canada, Chile, Czech Republic, Dubai, France, Germany, Hong Kong, Hungary, Iran, Italy, Japan, Lithuania, New Zealand, Norway, Oman, Poland, Portugal, Singapore, Spain, Slovenia, Switzerland, Taiwan, Thailand, Trinidad and Tobago, and the USA.
Our understanding is that all of these countries routinely offer pregnant women screening tests for GBS carriage during pregnancy, with the exception of Australia (where one state uses a risk-based prevention strategy and the remaining 5 out of the 6 States screen) and New Zealand (which uses a risk-based prevention strategy).
Isn’t the UK rate of GBS infection in newborn babies the same as countries that screen?
Well, no actually.
For 2014-5 in the UK & Republic of Ireland, the rates were 0.57 for early-onset GBS infection and 0.37 for late onset GBS infection per 1,000 live births (click here – page 11).
Not all countries publish data, but in the USA, for example, screening has reduced the rate of GBS infection in newborn babies (early onset) to 0.22 per 1,000 live births and for babies aged 7-90 days (late onset) to 0.25 in 2016 (click here). The US rate had been much higher before prevention measures were introduced.
Worldwide, the estimate rate of early-onset GBS infection is 0.41 per 1,000 live births, and for late-onset GBS infection 0.26 per 1,000 live births for 2015 (click here).
The rate in the UK & Republic of Ireland for early onset GBS infection is over 2.5 times the US rate, and almost 1.5 times the worldwide rate.
How many people carry group B Strep?
GBS is a normal bacterium which is carried by 20-40% of adults, most commonly in the gut, but for up to 25% of women, in the vagina too.
Not everyone carries GBS. Pregnancy does not ‘bring it on’ or cause a ‘flare-up’. The bacteria can be passed from mother to baby around labour and this causes no problems for most babies, although for a small number it can be life-threatening, causing blood poisoning, pneumonia and meningitis.
Are the tests for GBS colonisation (carriage) reliable?
It depends which test you’re using.
The tests widely available in the NHS (the standard direct plating tests) are not very reliable when they give a negative result – they give a negative result up to 50% of the time when they should be positive. On the other hand, a positive conventional test result is very reliable (they rarely find something that’s not there).
The GBS-specific ECM (enriched culture medium) tests are highly reliable and are good predictors of your GBS carriage status for 5 weeks after the swabs have been taken. The ECM test is the test recommended for use by the Royal College of Obstetricians & Gynaecologists for women who carried GBS in their previous pregnancy. An increasing number of NHS trusts offer the ECM test to some or all pregnant women, as do private services, including offering home-testing packs – click here for more information.
If you are or have recently taken antibiotics, this may affect the test result so discuss this with your midwife or doctor. If you can, leave it for a couple of weeks after completing the course of antibiotics before testing.
Any test detecting group B Strep during your current pregnancy means you should be offered intravenous antibiotics as soon as possible once labour has started to protect your newborn baby from GBS infection.
GBSS fully endorses the availability of reliable antenatal testing for GBS carriage. We want ECM testing to be freely available to all pregnant women on the NHS. We don’t sell ECM tests, but signpost to reputable organisations that do – click here.
How do people become carriers of group B Strep?
Like many bacteria, GBS may be passed from one person to another through skin to skin contact, for example, hand contact, kissing, close physical contact, etc. As GBS is often found in the vagina and rectum of colonised women, it can be passed through sexual contact.
There are no known harmful effects of carriage itself and the GBS bacteria do not cause genital symptoms or discomfort. GBS carriage is not a sexually transmitted disease, nor is GBS carriage a sign of ill health or poor hygiene.
No-one should ever feel guilty or dirty for carrying GBS – it’s normal.
Because GBS may be passed from one person to another by skin to skin contact, everyone (regardless of whether they know they carry GBS) should wash their hands properly and dry them properly before handling a newborn baby.
I’ve been told group B Strep carriage comes and goes so often it’s not worth testing for, is that right?
Well, that’s simply wrong. Research has shown that, whatever the result of a sensitive test for GBS carriage, your status is hugely likely to be the same for the next 5 weeks. After that, the predictiveness wanes a bit – though it doesn’t plummet like a stone. This is why testing is recommended in the last 3-5 weeks before your anticipated delivery date. This is usually at 35-37 weeks of pregnancy – so the results remain predictive for when you are most likely to give birth and the test result should be available before your baby arrives.
Do remember that the standard NHS test – with samples taken using a high vaginal swab, or HVS, which are then cultured on a standard agar plate – was not designed specifically for detecting GBS carriage, and is not great at doing so. Research has found this method will miss up to 50% of the women carrying GBS when the swabs are taken. A positive test result obtained by this method is highly reliable, but if you get a negative result, you can’t be sure it’s because the GBS wasn’t there, or whether the test simply didn’t detect it.
I’ve been offered a test for group B Strep carriage on the NHS
It’s very important to find out which test they’re using. Not all tests to detect group B Strep carriage are equally good, unfortunately. Any positive test result is highly reliable as tests usually don’t find something that isn’t there, but a negative result can be less reliable. So do find out if you’re being offered a standard ‘non-specific’ test or the GBS-specific Enriched Culture Medium or ECM test.
The general, non-specific test usually just takes swab samples from the vagina which are sent off to the lab for processing – this test misses up to half of the women carrying GBS when the swabs are taken. The GBS-specific ECM is the ‘gold standard’ for detecting GBS carriage and means taking swab samples from the low vagina and rectum which are sent off to the lab for processing using an enrichment process – this test is much more sensitive. If your health professional isn’t sure which it is, then it’s likely to be the standard ‘non-specific’ test. Read more about the different tests for GBS carriage by clicking here.
For information about where you can obtain the ‘gold standard’ ECM test, click here.
Do I have to do the GBS test at 35-37 weeks of pregnancy?
No. The ECM test has been found to be a good predictor of your GBS carriage status for the 5 weeks following testing, so the aim is to test in the 5 weeks before you go into labour and give birth. Because no-one can tell you exactly when that is, 35-37 weeks is used as the best estimate of when that’s likely to be.
Doing the test earlier means that the gap between testing and giving birth is more likely to be longer, so there’s a greater chance your carriage status will have changed by then (so you may either pick up or lose GBS carriage in the intervening weeks).
Tests done after 37 weeks will still give you a very good indication of what your GBS carriage status is for the next 5 weeks but there’s an increasing chance that your results will not be available when you go into labour, so your baby may arrive before the results. It would be a shame to do the test then get the results after your baby is born!
So 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..
Read about the different tests for GBS carriage by clicking here.
What if I get a negative result from a test for GBS carriage?
A woman who has a negative result from a sensitive test for GBS carriage (so either an ECM [Enriched Culture Medium] or PCR [Polymerase Chain Reaction] test) within 5 weeks of delivery does NOT need to be offered intravenous antibiotics in labour to prevent GBS infection in her newborn baby, although antibiotics may be indicated for other reasons. Research shows that an ECM test performed within 5 weeks of delivery giving a negative result was 96% predictive of GBS not being carried at delivery (4% of women acquired carriage between testing and delivery) so the risk of gaining carriage between doing the test and giving birth is very small.
If a woman has not had a negative result from a sensitive test for GBS carriage OR a result from the less reliable conventional test has been negative during the pregnancy, she should be offered intravenous antibiotics from the start labour if one or more risk factors are present (click here for more information).
A woman who has previously had a baby who developed GBS infection should ALWAYS be offered intravenous antibiotics in subsequent labours, from the onset of labour or waters breaking until delivery, regardless of any test results (although if she’s had a negative result from a sensitive test within the last 5 weeks of pregnancy, she may choose not to have them).
A woman who has had any positive test result (from the urine, vagina or rectum – with an NHS test or a private test) during the current pregnancy should be offered intravenous antibiotics from the start of labour or waters breaking until delivery (although if she’s had a negative result from a sensitive test for GBS carriage within the last 5 weeks of pregnancy, she may choose not to have them).
Read more about the different tests for GBS carriage by clicking here.
Do I need antibiotics if GBS is found on a vaginal or rectal swab?
If group B Strep has been found during your pregnancy from a vaginal or rectal swab, no treatment is recommended until labour starts, when you should promptly be offered intravenous antibiotics*.
Antibiotics have been shown to be highly effective at preventing GBS infection in newborn babies when they’re given as soon as possible once labour has started and at regular intervals until the baby is born. This dramatically reduces the risk of GBS infection in a newborn baby. To find out more about our medical panel’s recommendations for prevention, click here.
*All UK national guidelines recommend that Mum should be offered intravenous antibiotics in labour if GBS has been detected during the current pregnancy.
I carry group B Strep in my vagina. Does my partner needs to be tested?
No. Carrying GBS is normal and does not need treatment. Between 20-40% of adults carry GBS, without symptoms – you don’t need to be tested for it, nor do you (or he) need antibiotics for it. GBS is not a sexually transmitted disease. Carrying GBS is not a disease.
I have vaginal symptoms – are these caused by group B Strep?
We know of no convincing evidence that shows carrying GBS causes vaginal symptoms. Carrying GBS is asymptomatic – it is not associated with symptoms. To confirm you are carrying GBS, you need to test and the sensitive ECM test is the test recommended to detect GBS carriage. A GBS positive result from a vaginal swab means the vagina was colonised with GBS when the swab was taken and does not mean GBS is the cause of those symptoms.
Antibiotics for carrying GBS is not helpful until labour starts. No antibiotics tested so far have been shown to eradicate GBS carriage reliably from the body so, even if antibiotics were to clear the GBS carriage from the vagina (and they may not), recolonisation from the intestines will occur.
The time when antibiotics have been proven to be effective at preventing GBS infection in newborn babies is when they are given intravenously to the mother once her waters have broken or as soon as labour has started and at intervals until she has given birth.
Will antibiotics get rid of group B Strep carriage from my vagina during pregnancy?
Not necessarily, and, even if they do, it’s only temporary – recolonisation will occur. There’s no evidence that taking antibiotics before labour reduces GBS infection in newborn babies either. Studies have shown no substantial difference in carrying GBS at delivery between women treated with antibiotics during pregnancy and those not treated. Antibiotics have been proven to be highly effective at stopping GBS infections in newborn babies when given intravenously to the pregnant woman as soon as her waters have broken or labour has started.
Should I take antibiotics before I get pregnant to get rid of the group B Strep?
No antibiotics tested so far seem able to do this reliably. Antibiotics may temporarily eradicate vaginal carriage of GBS, but carriage in the intestines will remain and recolonisation of the vagina will occur.
Do I need antibiotics if group B Strep is found in my urine?
Generally yes, but GBS detected in the urine does not always mean an infection is present, particularly when the level of the bacteria detected is low – sometimes it is just that the urine has picked up some GBS from vaginal or rectal carriage on its way out of the body.
If GBS is detected from a urine sample or from a vaginal or rectal swab at any level during pregnancy, you should be offered intravenous antibiotics once labour has started.
Treatment for GBS found in the urine depends on the level of GBS found and whether or not you have any symptoms. When detected during pregnancy:
- GBS in the urine ≥ 10^5 cfu/ml with or without Mum having symptoms of a urinary tract infection (for example, frequent or painful urination or fever) – this is considered as bacteriuria and treated with oral antibiotics. Mum should also be offered intravenous antibiotics when she goes into labour.
- GBS in the urine ≥ 10^4 cfu/ml with Mum have symptoms of a urinary tract infection – this is treated with oral antibiotics. Mum should also be offered intravenous antibiotics when she goes into labour.
- GBS in the urine 10^4-10^5 cfu/ml with Mum having no symptoms of a urinary tract infection – usually the midstream stream urine test (preferably with labia separated) is repeated. If the same level of GBS is still present, then treatment will be considered. Mum should also be offered intravenous antibiotics when she goes into labour.
- GBS in the urine ≤ 10^3 cfu/ml or less with Mum having no symptoms of a urinary tract infection – this is considered to be contamination and no treatment is offered. Mum should be offered intravenous antibiotics when she goes into labour.
When treatment is recommended for GBS bacteria in the urine during pregnancy, oral antibiotics are given, usually for 5 days. The urine should be retested 7-10 days after finishing the antibiotics and treatment repeated if necessary until the urine tests come back clear.
Treatment for a urine sample which detects the growth of GBS in the urine ≥10^5 cfu/ml, whether you have symptoms of a urine infection or not, is important since, if left untreated, such infections can cause kidney damage and have been linked to preterm labour.
GBS detected from a urine sample or from a vaginal or rectal swab at any level during pregnancy means Mum should be offered intravenous antibiotics once labour has started.
If I had a positive result for group B Strep early in my pregnancy. Should I be tested again?
If you have had a positive GBS test result (from the vagina, rectum or in a urine sample) during the current pregnancy, you should be offered intravenous antibiotics from the onset of labour until delivery (antibiotics are usually recommended at the time GBS is detected in urine samples – see above).
If the positive result was early in your pregnancy, you may not still be carrying GBS by the time your baby is born. If you want to find out whether you are still carrying GBS, you can have a sensitive ECM test at 35-37 weeks. If that test result is negative, then intravenous antibiotics are not indicated, since research shows that a sensitive test giving a negative result within 5 weeks of delivery is highly predictive of Mum not carrying GBS during those 5 weeks. The risk of acquiring carriage between doing the test and giving birth is very small.
Click here for the availability of sensitive tests for GBS carriage.
Should I be tested regularly for group B Strep?
No. Although a positive result is reliable, a negative result from the standard non-specific test often used within the NHS is unreliable – it misses up to 50% of those carrying GBS when the test is done. So, repeat NHS tests are unlikely to be helpful – each time, you’d only have about a 50% chance of detecting GBS if it’s there, and a negative result isn’t really helpful: it either means GBS isn’t present or that it was and the test missed it.
If you have had any positive test result for GBS during your current pregnancy, you should be offered intravenous antibiotics from the start of your labour, until delivery. Since updates to the Royal College of Obstetricians and Gynaecologists guidelines in September 2017 the ‘gold standard’ ECM test for GBS carriage is increasingly available from NHS hospitals. However, we expect there to be some delay before the test is available in all UK hospitals, it is worth checking with your health professionals.
The test is also available privately – for details, click here.
I carried group B Strep in my last pregnancy – my baby was fine. Do I need IV antibiotics this time?
Carrying GBS in your last pregnancy isn’t a good indicator that you’re carrying it this time, though you are more likely to (about double the chance of carrying it this time compared with the background population).
If you carried GBS in a previous pregnancy and your baby was not unwell, a new recommendation in the September 2017 Royal College of Obstetricians & Gynaecologists’ GBS guideline is that you should be offered either:
- intravenous antibiotics as soon as labour starts
- an ECM test at 35-37 weeks of pregnancy, with the intravenous antibiotics offered as soon as labour starts if the test result is positive.
Taking antibiotics is never without risk – so it is important they are used only when the potential benefit outweighs the risk. The only way to find out if you’re carrying GBS during your pregnancy is to test for it during that pregnancy. Although the ECM test is not yet widely available within the NHS, it is available privately from around £35 for a home-testing pack. For information on availability, click here.
What are the chances of my baby developing a group B Strep infection?
In the UK, just under one in every 1,000 babies between the ages of 0-90 days and born during 2014/5 were reported as having had a group B Strep infection. Approximately 6 in every 10 of those babies developed in the first 6 days of life, with the remaining 4 in every 10 developing GBS infection between ages 7-90 days. UK research has suggested this may be a serious underestimate of the true incidence of GBS infection in newborns, which could be as high as 3.6 per 1,000.
The following are estimates of the chances a baby in the UK will develop GBS infection in their first 6 days, assuming no preventative measures are taken and assuming no other risk factors are present:
- 1 in 5,000 where a woman has had a negative sensitive test for GBS carriage in the last 5 weeks of pregnancy
- 1 in 1,000 where a woman’s GBS carriage status is unknown
- 1 in 400 where the woman is carrying GBS during the pregnancy
- 1 in 100 where the woman has had a previous baby infected with GBS.
If a woman who carries GBS is given the recommended antibiotics in labour, the baby’s risk is reduced by an estimated 85-90%. So, again assuming no other risk factors are present:
- 1 in 4,000 where the mother carries GBS during pregnancy
- 1 in 1,000 where the mother has previously had a baby infected with GBS.
The large majority of pregnancies can be managed so that babies are protected and born free from early-onset GBS infection.
Must I have intravenous antibiotics if I’ve had a positive result for group B Strep during this pregnancy?
If you have had any positive GBS test result from swabs taken the vagina or rectum during the current pregnancy, you should be offered intravenous antibiotics from the onset of labour or waters breaking until delivery. However, you may choose not to have them if there are no additional risk factors – only a small percentage of babies born to women carrying GBS will develop the infection. However, if you decide against antibiotics, it would be prudent for the baby to be observed by trained staff for at least 12-24 hours.
However, if the positive test result was from a urine sample, this means that the GBS was more invasive, and so antibiotics will be recommended.
If I have the IV antibiotics in labour, do I have to be attached to a drip the whole time?
No, the antibiotics are given intravenously through a cannula (usually in the back of your hand). They’re given either by slow injection over 5-10 minutes or so, or through a drip which can take 20 minutes or so. Once the antibiotics have been given, the cannula is plugged and you are then able to move around as you wish, until the top up dose is due.
What are the potential risks of antibiotics?
Taking antibiotics should not be done lightly – they can have side effects that need to be considered in relation to the potential benefits and it is important that you tell your health professionals if you have an allergy to penicillin (or any other antibiotic). If you are allergic to penicillin, there are alternative antibiotics.
Although good data is hard to find on this subject, the generally quoted estimated risks for penicillin are:
- 1 in 10,000 of the mother developing a severe allergic reaction (anaphylaxis*); and
- 1 in 100,000** of the mother developing fatal anaphylaxis, resulting in her death.
Severe complications can occur in the unborn baby even when the anaphylaxis developed by the mother is not life threatening, although this risk is probably overstated.
*Anaphylaxis is a severe, potentially life-threatening allergic reaction that can develop rapidly. It is also known as anaphylactic shock. Signs of anaphylaxis include itchy skin or a raised, red skin rash, swollen eyes, lips, hands and feet, feeling lightheaded or faint, swelling of the mouth, throat or tongue, which can cause breathing and swallowing difficulties, wheezing, abdominal pain, nausea and vomiting, collapse and unconsciousness.
**Although often quoted, these figures are generally accepted as being a significant over-estimate of the risk – a recent paper stated that, in the US between 1997 (the year after the CDC recommended intravenous antibiotics in labour for women whose babies were at higher risk of developing GBS infection) and 2001, an estimated 1.8 million women were given penicillin in labour and no deaths occurred, so an estimate of a 1 in 100,000 risk of death from penicillin anaphylaxis is likely to be an over-estimate. The prevention of neonatal group B streptococcal disease. MR Law, G Palomaki, Z Alfirevic, R Gilbert, P Heath, C McCartney, T Reid, S Schrag on behalf of the Medical Screening Society Working Group on GBS Disease. J Med Screen 2005;12:60-68.
Whenever antibiotics are taken, there are always risks of antibiotic resistance developing. When antibiotics are given to pregnant women, this could affect the mother and her baby. When antibiotics are given around birth and in the early weeks of life, there is the chance they may increase the likelihood of the baby developing allergies. Although a lot of press space is given to this, data is unfortunately lacking on whether it’s the giving of antibiotics that causes the allergies, or whether there are other reasons (for example, genetics, environment, disease, etc.). This is yet another area where more research is needed.
Bearing all this in mind, you need to weigh up whether you consider the risks are acceptable in comparison with the potential benefits and, if so, in what circumstances you would want to the antibiotics.
Antibiotics – more harm than good?
Sometimes we’re asked whether antibiotics in labour against GBS infection in the newborn baby do more harm than good. The source of concern is often a 2008 article published in The Lancet about the ORACLE II trial. This reported the long-term effects of antibiotics given to women in threatened preterm labour. Their babies were followed up to age 7. The study found that low-dose, broad spectrum, oral antibiotics for up to ten days produced no benefits and were associated with about double the risk of the baby developing cerebral palsy for reasons that are not fully understood. In contrast to the regime used in the ORACLE II trial, women given antibiotics as preventative medicine against GBS infection in their newborn baby are given high-dose, narrow-spectrum (usually penicillin), intravenous antibiotics at 4 hourly intervals from the start of labour until the baby is born (so for hours not days). This has been shown to reduce the risk of early onset GBS disease by about 90%, without any known long-term side-effects on the baby.
There has been a lot of publicity recently about the inappropriate and excessive use of antibiotics (sparked by Prof Dame Sally Davies DBE, Chief Medical Officer, England – click here). We at GBSS are well aware of the risks of excessive use of antibiotics and have worked hard to stop misconceptions which result in their being given inappropriately – for example, in an erroneous attempt to eradicate carriage.
Research has shown that intravenous antibiotics (ideally penicillin), given in labour to women whose babies are at higher risk of developing GBS infection, is highly effective at reducing the risk of GBS infection in newborn babies, without any known long-term side-effects on the baby, and no apparent tendency to increase antibiotic resistance. Indeed, GBS has remained sensitive to penicillin for over 60 years.
I don’t want antibiotics in labour – are there natural alternatives?
Our medical advisory panel members are not persuaded that any therapy other than antibiotics in labour is effective in preventing early onset GBS disease.
One question we have been asked a lot recently is whether raw garlic, inserted into the vagina, will reduce the likelihood of GBS infection in a newborn baby. There is no good evidence that garlic will prevent GBS colonisation and, since the reservoir for GBS colonisation is the gut, garlic vaginally won’t impact colonisation there.
Unfortunately, although there is much discussion on this subject, particularly online, there simply are no natural, homeopathic or alternative medicines for which there has been good research and proof that they are effective at preventing group B Strep infection in newborn babies. It this changes, we’ll issue an update.
Is vaginal disinfection an alternative to intravenous antibiotics in labour?
The idea that vaginal disinfection at the time of labour may eradicate GBS colonisation in the vagina has been investigated, particularly in Scandinavian countries. The advantages are that the potential risks associated with antibiotics are avoided whilst, at the same time, the vaginal disinfection may reduce neonatal colonisation with GBS. However, reduced neonatal colonisation would have no impact on the majority of babies who develop early onset GBS infections, since these babies are usually infected or colonised before they come through the birth canal. A study of over 5,000 labouring women found that using maternal chlorhexidine vaginal wipes during labour and neonatal chlorhexidine wipes did not reduce death in the mother or baby, or sepsis in the baby. It is also questionable how acceptable using chlorhexidine would be to pregnant women – it is not an innocuous substance and could potentially be harmful to the baby, particularly if the waters have broken or the baby is preterm.
The members of our medical advisory panel are not persuaded that any therapy other than antibiotics in labour is effective in preventing early onset GBS disease.
I’m worried I won’t get 4+ hours of IV antibiotics before my baby is born
A very small study* showed giving intramuscular penicillin eradicated GBS colonisation for at least 6 weeks in 75% of women known to carry GBS. So far, this very small study (50 of 78 women received intramuscular antibiotics) has not been repeated, so it is difficult to give advice based upon this data.
For women known to carry GBS where it is not expected that the intravenous antibiotics can be given for at least 4 hours before delivery, an intramuscular injection of 4.8 MU (2.9 g) of Penicillin G at about 35 weeks of pregnancy may be useful in addition to intravenous antibiotics given from the onset of labour or membranes rupturing until delivery to try to eradicate GBS colonisation until after delivery.
Regardless of whether you have intramuscular antibiotics to try to eradicate GBS colonisation, it is recommended that all women in higher risk categories be offered intravenous antibiotics from the onset of labour or waters breaking, plus at 4 hourly intervals until delivery.
There are downsides of intramuscular penicillin – the injection is painful, there is a small risk of an allergic reaction and of antibiotic resistance developing (see below). These risks are repeated with the intravenous antibiotics given in labour.
For intramuscular antibiotics, there are no known alternatives to penicillin for penicillin-allergic women.
*(Bland ML, Vermillion ST, Soper DE. Late third-trimester treatment of rectovaginal group B streptococci with benzathine penicillin G. Am J Obstet Gynecol 2000 Aug;183(2):372-6)
Can group B Strep cause preterm birth, stillbirth, and late miscarriage? Should I take long-term antibiotics?
Along with many other bacteria found in the vagina, GBS can cause infection of a baby in the womb, which can result in preterm birth, stillbirth and late miscarriage. However, thankfully these events are not common and GBS is a rare cause of them. These complications are usually caused by a variety of factors other than GBS: genetic defects, gynaecological problems, other infections, etc. If a woman has had any of these problems in the past, she should make sure these possibilities are investigated fully by a consultant obstetrician at booking (or before) regardless of whether or not she is colonised with GBS.
For the antibiotics tested so far, their use throughout pregnancy does not prevent preterm delivery due to any cause, including GBS. Also, the effects of long-term antibiotics on the baby during pregnancy have not been assessed; although we know that short courses of, for example, amoxycillin, seem to be exceptionally safe.
What are the signs that group B Strep is affecting my unborn baby?
If your pregnancy is progressing normally, then there is no reason to suspect group B Strep is infecting your baby. Both Mum and Baby have natural defences against the baby developing GBS infection before labour starts or waters break. In the unlikely event a GBS infection does develop, Mum will usually go into labour or her membranes will rupture. And that’s the time to get to hospital as quickly as you can to receive the intravenous antibiotics to give your baby the best protection possible. And, of course, if you are concerned about anything when you’re pregnant (including if you experience reduced fetal movements which can be another sign that baby is in distress), you should seek advice from your midwife in the first instance. If she’s not available, then do contact your maternity unit – they’re there to help you.
Should I be induced, with the IV antibiotics starting as I’m induced?
Our medical advisers do not recommend induction for anyone as a way of combating GBS infection in babies. Carrying GBS, or your baby being at raised risk of GBS infection is not a reason to be induced.
You should be offered immediate induction plus the intravenous antibiotics in labour if f you are known to be carrying GBS and your waters break before labour starts, because of the increased risk of early onset GBS infection developing in babies after prolonged rupture of membranes.
If you live a long way from the hospital or have a history of very fast labours, induction may be one way to try and ensure you get sufficient intravenous antibiotics in labour. However, induction is not without risk itself, especially before the due date. You should discuss the potential risks and benefits of induction with your obstetrician, because they will vary dependent upon your personal circumstances.
If you need to be induced, the recommended intravenous antibiotics should be started as soon as possible once labour has started or waters have broken (naturally or artificially), and should be repeated 4-hourly until your baby is born, and ideally for at least 4 hours before delivery.
Will a Caesarean prevent group B Strep infecting my baby?
Not necessarily. Caesarean sections do not eliminate the risk of GBS infection since the bacteria can cross intact amniotic membranes to set up an infection in the baby, although they do reduce the risk.
Caesareans are not recommended as a method of preventing GBS infection in babies: they don’t eliminate the risk to the baby, there are significant risks associated with a Caesarean section, and the recommended intravenous antibiotics during labour are both low risk and highly effective.
If I’m having a Caesarean, do I need antibiotics before it to protect against group B Strep infection in my baby?
Caesarean sections are not recommended as a method of preventing GBS infection in the baby. They do reduce but not eliminate the risk of GBS infection to the baby, since GBS can cross intact amniotic membranes to set up an infection in the baby. There are risks associated with Caesarean sections; plus the recommended intravenous antibiotics during labour are highly effective and low risk.
If you are having a Caesarean section, our medical panel’s recommendations with regard to GBS are as follows:
Elective Caesareans If a baby is at higher risk of developing GBS infection and the mother is having an elective Caesarean AND is in labour OR her waters have broken, she should be offered the recommended intravenous antibiotics as soon as possible after the start of labour. The baby would only need intravenous antibiotics against GBS infection if born prematurely or if there are signs of possible infection in either the mother or the baby.
Emergency Caesareans If a woman carries GBS or has previously had a baby infected with GBS and needs an emergency Caesarean, she should be treated as for an elective Caesarean – no intravenous antibiotics are indicated against GBS unless she is in labour or her waters are broken. If she is in labour, she should be treated as for a normal labour up until the time when an emergency Caesarean section becomes necessary, when she should be delivered immediately. Any treatment of the baby for GBS would follow normal neonatal/paediatric recommendations.
Are membrane sweeps safe for women who carry group B Strep?
Using a gloved finger passed through the cervix (neck of the womb) to separate the baby’s membranes from the lower part of the uterus is known as a ‘membrane sweep’. In women who are at or beyond the due date, it encourages spontaneous labour and can enable about 10% of women to avoid an artificial induction of labour.
There is no good evidence that membrane sweeps are harmful in women known to carry GBS. The results of trials of membrane sweeps don’t show any increase in problems caused by GBS in women having sweeps, and it is highly likely these trials would have included many women carrying GBS at the time.
However, there remains a theoretical risk that a membrane sweep might occasionally introduce GBS into the uterus, and so our medical advisory panel advises caution in using a membrane sweep for women known to carry GBS when there are other acceptable alternatives (for example, induction of labour with prostaglandin gel introduced into the vagina)
Group B Strep and artificial rupture of membranes (AROM)
Artificial rupture of membranes (AROM or amniotomy) is usually used to speed up labour, possibly shortening labour by about an hour, and usually resulting in contractions becoming stronger and more painful. We know of no contra-indications for AROM where Mum is known to carry GBS although, as it’s normally done once labour has started, you should already be receiving the 4 hourly antibiotics before AROM is done. The reason for the amniotomy should be discussed and consent should be given by the Mum before it is done.
Carrying group B Strep and water birth
There are no known contra-indications for a woman known to be carrying GBS having a water birth. As for all women carrying GBS during the current pregnancy, our medical advisory panel recommends they should be offered intravenous antibiotics from the onset of labour until delivery. It is not a good idea to get the cannula (which delivers the intravenous antibiotics to the mother) wet, but this can be managed – specially designed waterproof dressings are available which keep the site sterile and dry whilst still enabling the health professional to monitor the site visually. You can read an article about waterbirths by clicking here.
Carrying group B Strep and home birth
Our Medical Advisory Panel’s recommendations for stopping GBS infections in newborn babies are the same for home births as for hospital births – women whose babies are at higher risk of developing GBS infection should be offered intravenous antibiotics from the start of labour until delivery.
Home births are becoming increasingly popular and, if you want a home birth with intravenous antibiotics during labour until delivery, it may be possible for your midwife to give you intravenous antibiotics prescribed for you by your GP. This is not widely available. Some areas won’t permit intravenous antibiotics to be given at home – there is a small risk that you would get a severe allergic reaction to the antibiotics (see What are the potential risks of antibiotics? above) and, obviously, there is no intensive care unit nearby. The risk is small and the antibiotics make the chance of the baby developing group B Strep infection much smaller, but nevertheless your health professionals may be anxious. Of course, around 25% of women having home births probably carry GBS in their vagina at delivery without knowing it. This issue needs to be discussed with your medical team.
Oral antibiotics are not recommended for women for GBS carriage during pregnancy or labour. Quite simply, there’s no evidence that they prevent GBS infections in babies. If you have set your heart on a home birth, you may wish to consider having intramuscular antibiotics as outlined in I’m worried I won’t get 4+ hours of IV antibiotics before my baby is born above, though our medical advisory panel does not recommend them in lieu of intravenous antibiotics during labour, but they may be better than nothing if that really is the only alternative.
Group B Strep and breastfeeding
Our medical advisory panel strongly recommends you should be encouraged to breastfeed your baby, whether or not you have been found to carry GBS.
Although there have been isolated cases describing GBS infection possibly related to breast milk contamination, the advantages of breast feeding will, in our medical advisory panel’s opinion, greatly outweigh the remote risk of transmitting GBS via breast feeding. High hygiene standards need to be maintained for all breastfeeding mothers, with the hands and nipple areas being kept clean.
The intravenous antibiotics recommended for pregnant women during labour through to delivery to protect her unborn baby from GBS infection are safe for breastfeeding mothers.
If you develop mastitis or a breast abscess, you should seek medical advice regarding breast-feeding.
My baby’s at higher risk of developing group B Strep infection – what should happen after birth?
Babies born at increased/high risk to mothers who have received antibiotics for MORE THAN 2 hours before delivery should be:
- Carefully assessed by an appropriately trained Paediatrician or Advanced Neonatal Nurse Practitioner.
- If completely healthy, no antibiotics for the baby are required.
- A period of monitoring (12-24 hours) may be appropriate for those at highest risk of infection.
- Parents should be made aware of the early signs of infection and given a handout about GBS.
Babies born at increased/high risk to mothers who have received antibiotics for LESS THAN 2 hours before delivery should be:
- Examined thoroughly and investigated by a Paediatrician as appropriate.
- Observed for a minimum of 12 hours, ideally 24 hours.
- If completely healthy, no antibiotics for the baby are required (antibiotics should be administered if there is any doubt).
Babies whose gestational age is less than or equal to 36 completed weeks of pregnancy and are born by Caesarean section (not in labour, no broken waters) where antibiotics were given to the mother for less than 2 hours before delivery should be:
- Examined thoroughly by a Paediatrician and a full sepsis work up done.
- Started on intravenous antibiotics unless a robust examination determines baby is completely healthy.
- Reviewed at 48 hours.
For well babies at highest risk of infection, monitoring for 12-24 hours may be appropriate and this should be undertaken as a minimum if the baby is not screened and treated for infection.
If there’s any doubt about whether an infection is present, the baby should be started on intravenous antibiotics until it is known that he/she is not infected.
Early and Late Onset group B Strep infection
Around two thirds of GBS infections in babies are early-onset (developing in the baby’s first 6 days of life) and the remaining third are late-onset, occurring after the baby’s first 6 days. Most GBS infections show in the first 2 days of life, they are uncommon after a baby reaches one month old and very rare after age three months. Although intravenous antibiotics in labour are very effective at reducing the chance of a baby developing early-onset GBS infection, currently there are no known ways of preventing late-onset GBS infections so identifying signs and symptoms of these infections is vital for early diagnosis and treatment.
For more information about early- and late-onset GBS infections, including signs and symptoms, click here.
If a baby shows signs consistent with GBS infection or meningitis, call your doctor immediately. If your doctor isn’t available, go straight to your nearest Paediatric Casualty Department. If a baby has GBS infection or meningitis, early diagnosis and treatment are vital: delay could be fatal.
Is group B Strep infection linked with cow’s milk intolerance?
Cow’s milk protein intolerance is increasingly recognised in babies and is a manifestation of immune “dysregulation”. Most of the immune cells of the body are in the linings of the gut. Immature immune cells in the gut of the newborn, develop as a result of stimulation by “normal” gut flora, which live in harmony with each individual. “Dysregulation” means that the newborn immune system develops in an “unregulated” way, and so the gut does not become “tolerant” of “foreign” milk proteins such as those derived from cow’s milk. Emerging data suggests that there may be a link between antibiotic treatment of mothers and/or babies and immune dysregulation. This is not a confirmed link, just a possibility. It may be the result of exposure to antibiotics used to treat the infection, which alter the newborn baby’s gut flora, which consequently affects the generation of the “right” sort of immune responses. Alternatively, group B streptococcus may be the ‘wrong’ bacterium to stimulate normal immune development. This is an area where more research is needed.
Babies with suspected GBS infection should be given appropriate antibiotic treatment, as there could be far more serious consequences than milk intolerance, if infection is not promptly treated. Many babies who never had any antibiotic exposure either directly or via their mothers, also suffer milk protein intolerance. Babies will normally grow out of milk intolerance once the immune system matures, usually in the second 6 months of life.
Group B Strep and immunisation
GBS is not a factor in the decision as to whether you should be vaccinated against flu, regardless of whether you know you carry GBS or not.
We know of no evidence that babies born to women who carry group B Strep or who have recovered from a group B Strep infection should not receive the normal childhood vaccinations.
Group B Strep and seeding
The practice of ‘seeding’ babies born by Caesarean (putting a gauze swab in the vagina for 24 hours beforehand and then wiping the baby’s mouth and skin with that gauze after birth) is attracting attention. The hope is that exposure to bacteria will boost the baby’s immune system, thereby preventing illness and disease in the future, such as asthma and allergies.
The charity does not recommend this practice because there is no properly conducted clinical trial that has clearly evaluated the risks and benefits of seeding. To date, published data are very small and have not shown evidence of benefit – a number of trials are underway, and we look forward to seeing the results once published.
In the UK, where testing for group B Strep carriage is rarely available in the NHS, there is the potential Mums could inadvertently be exposing their babies to this bacterium, as well as others such as virulent coliforms, and viruses. While most babies exposed to group B Strep won’t develop infection – and we have not heard any reports of babies developing GBS infection as a result of this practice – it remains a theoretical risk, and of course group B Strep infection can be devastating.
This is yet another reason why good quality tests for group B Strep carriage should be made available to all pregnant women so they can make an informed decision about which is right for them and their babies.
I want more details on my child’s group B Strep infection – how can I get them?
If your baby developed a group B Strep infection, you may have questions about the care you and/or your baby received, particularly if you feel the infection could have been avoided. It is natural to want to understand better what happened. You should ask for (and are legally entitled to) a copy of your and your baby’s medical notes and will probably find it helpful to review them with the relevant health professionals so that they can explain what everything means.
Health professionals have a “duty of candour” to their patients. This includes being open and transparent about what happened, and telling you about things that could have been done differently. You can read more about this here.
All babies born at term and admitted unexpectedly to the neonatal unit undergo review and a Serious Incident Report or “root cause analysis” (RCA) report is made. This report should be shared with you.
Your hospital may invite you to meet with a senior obstetrician (pregnancy specialist), midwife and/or paediatrician/neonatologist (specialist in looking after newborn babies). If they haven’t, you can choose to contact them and request such a meeting. If you’re not sure of the name of your obstetrician or your baby’s paediatrician, you can make your request via the PALS (Patient Advice and Liaison Services), or to the Clinical Director for the service (maternity or neonatal or both).They have a duty ensure that your request is dealt with appropriately. It is very reasonable to ask for a meeting to explain what happened.
If you have any worries that the hospital’s health professionals are not giving you the full facts, you can ask for a report from a doctor from another hospital. This will usually be an obstetrician and/or neonatologist. The request is probably best made in writing to the Chief Executive of your Trust. Their contact details will be on the hospital website, or can be obtained from PALS.
If you feel that things were not done properly, then you have the right to go to a solicitor and ask them to investigate on your behalf. They will usually expect you to have already taken the steps described above to get as much information as possible, so that they can give you an opinion as to whether you might have a case which can be taken to Court. Legal processes are often very stressful for parents and can be expensive.
Unless a baby needs long-term care, many parents are satisfied with a proper explanation of what happened, and an apology for any mistakes made, especially if (as will happen in most cases) the baby makes a full recovery.
How can I make a complaint?
Sometimes things go wrong and nothing could have been done to prevent it. Sometimes that’s not true. Sometimes we can learn from mistakes that have been made. If sadly something has happened that means you are considering making a complaint to the NHS about your or your baby’s treatment, or if you’re considering taking legal action, please click here.
I’m allergic to Penicillin – is there an alternative to use in labour?
If you are allergic to penicillin, provided you have not had a severe allergy to penicillin, a cephalosporin should be used. If you have had a severe allergy to penicillin, vancomycin should be used. Please discuss this with your midwife or doctor.