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.
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 – it’s it’s been 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.
Our understanding is that all of these countries routinely offer pregnant women screening tests, 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).
Well, no actually. Not all countries publish data on their incidence of GBS infection, but for example in the US, the rate for GBS infection in newborn babies (early onset) was 0.24 per 1,000 live births and for babies aged 7-90 days (late onset) it was 0.27 (click here). For 2014 in England, Wales & Northern Ireland, the rates were 0.42 for early-onset and 0.24 for late onset per 1,000 live births. The US rate had been much higher before prevention measures were introduced, but now the rate in England, Wales & Northern Ireland for early onset GBS infection is 75% higher than in the US.
Not everyone carries GBS and pregnancy does not ‘bring it on’ or cause a ‘flare-up’ of group B Strep. It can be passed from mother to baby during labour and, although this causes no problems for most babies, for a small number it can be deadly, causing blood poisoning, pneumonia and meningitis.
The standard direct plating tests widely available in the NHS are not very reliable when they give a negative result – they give a falsely 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). See Which Test for GBS?
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. We’ve listed the NHS trusts we understand offer the ECM test to some or all pregnant women, together with private sources, including home-testing packs – click here for more information.
Any positive result during the 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 have no financial links with any laboratory. We hope all laboratories will offer the ECM test and, as they do, we’ll provide details of their services here.
There are no known harmful effects of carriage itself and, since 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.
Some of the confusion of UK health professionals may stem from the fact that the standard swabbing method (high vaginal swabs, or HVS) and the standard culture method (direct plating) used by the NHS were not designed specifically for detecting GBS and are not great at finding it. Research has found that using high vaginal swabs and the direct plating method of culture will miss up to 50% of the women carrying GBS at delivery. Clearly 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 isn’t there or whether the test simply didn’t detect it.
Read more about the different tests by clicking here.
For information about where you can obtain the ‘gold standard’ ECM test for group B Strep carriage, both on the NHS and privately, click here.
If the test is taken earlier than 35 weeks, then the chance that you will go into labour more than 5 weeks after that time and so your carriage status is more likely to have changed by then (ie you may either pick up GBS carriage, or have lose it in the intervening weeks). After 35 weeks, research has shown that you are much more likely to go into labour in the next 5 weeks, so your GBS carriage status is much more unlikely to change.
If the tests are taken later than 37 weeks, they will still give you a very good indication as to your carriage status for the next 5 weeks, during which time you are very likely to give birth. However, there is a chance that your results will not be ready when you go into labour, and your baby may arrive before them. It would be a shame to do the test then get the results after your baby is born!
So the 35-37 weeks window is suggested as being potentially the best time to test – having said that, it won’t suit everyone.
If a woman has not had an ECM or PCR test result OR the less reliable conventional test has been negative during the pregnancy, she should be offered intravenous antibiotics from the onset of labour if one or more risk factors (listed at Risk Factors for GBS) are present.
A woman who has previously had a baby who developed GBS infection should ALWAYS be offered intravenous antibiotics in subsequent pregnancies, from the onset of labour or membrane rupture until delivery, regardless of any test results.
And a woman who has had any positive test result (from the urine, vagina or rectum) during the current pregnancy should also be offered intravenous antibiotics from the onset of her labour or membrane rupture until delivery.
*All national guidelines published in the UK recommend that Mum should be offered intravenous antibiotics in labour if GBS has been detected during the current pregnancy.
Antibiotics for GBS carriage are not indicated (until labour starts). No antibiotics tested so far have been shown to eradicate GBS reliably from the body so, even if antibiotics clear the GBS colonisation of the vagina (and they may not), recolonisation from the intestines will occur. The time when antibiotics have been proven to be effective against GBS infections in 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 delivery.
Antibiotics during pregnancy for GBS carriage are not indicated. GBS cultured from a vaginal swab show the vagina is colonised with GBS, not infected. No antibiotics tested so far have been shown to eradicate GBS reliably from the body so, even if antibiotics clear the GBS colonisation of the vagina (and they may not), recolonisation from the intestines will occur. Evidence shows taking antibiotics neither gets rid of GBS carriage nor reduces the incidence of GBS infection in newborn babies. 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 membranes have ruptured or labour has started.
Treatment for GBS found in the urine depends on the level of GBS found in the urine and on whether or not Mum has 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.
However, if the positive result was early in your pregnancy, you may have lost carriage by the time your baby is born. If you want to find out whether you are still carrying GBS, you can have a sensitive test at 35-37 weeks. If the sensitive test result is negative, then intravenous antibiotics are probably not indicated, since research shows that a sensitive test giving a negative result within 5 weeks of delivery is highly predictive of the mum not carrying GBS at delivery. The risk of acquiring carriage between doing the test and giving birth is very small.
The conventional test available on the NHS is unreliable – it misses up to 50% of GBS carriers. There is a reliable test but this is not available from most NHS hospitals, although it is available from two private laboratories which offer a postal service. See Which Test for GBS?
And if you get another positive result from the conventional test, all it tells you is that you are still carrying GBS. If it gives you a negative result, all it tells you is you may not be still carrying GBS (but remember the negative test results aren’t very reliable). Neither of these results should make any difference to your being offered intravenous antibiotics in labour.
If a reliable test result is not available and labour starts after 37 weeks of pregnancy, then the view of our medical panel is that previous carriage status should be treated as an additional risk factor (increasing the risk of a baby developing GBS infection where preventative antibiotics in labour are not given from an estimated 1 in 1,000 in the general population, to approximately 1 in 500 for a woman whose current GBS status is unknown, but where GBS was isolated before the current pregnancy). Our medical panel’s view is that the ‘previous carrier’ risk factor alone is insufficient to recommend offering intravenous antibiotics in labour against GBS infection in the baby, unless another clinical risk factor was also present.
- 1 in 1,000* where the woman is not known to be a carrier of GBS;
- 1 in 400 where the woman is carrying GBS during the pregnancy;
- 1 in 300 where the woman is carrying GBS at delivery; and
- 1 in 100 where the woman has had a previous baby infected with GBS.
*This is a broadly accepted estimate of the number of GBS infections in newborn babies that would occur if no preventative intravenous antibiotics in labour are given and this estimate has been used throughout this document. Recent UK research suggested this may be a serious underestimate of the incidence of GBS infection in newborns, which could be as high as 3.6 per 1,000.
If a woman who carries GBS is given antibiotics during labour through delivery in accordance with our medical advisory panel’s recommendations at Prevention, the baby’s risk is reduced significantly.
- 1 in 8,000 where the mother carries GBS during pregnancy;
- 1 in 6,000 where the mother carries GBS at delivery; and
- 1 in 2,200 where the mother has previously had a baby infected with GBS.
The vast majority of pregnancies can be managed so that babies are protected and born free of GBS infection.
21. Must I have intravenous antibiotics if I’ve had a positive result for GBS during this pregnancy?
Although good data is hard to find on this subject, the generally quoted estimated risks for penicillin are:
- 1 in 10 of the mother developing a mild allergic reaction, such as a rash;
- 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.
And 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.
*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 be offered antibiotics.
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, or in a labour following a positive result from a previous pregnancy where the baby was unaffected.
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.
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.
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 help with that at all
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.
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.
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.
1(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)
28. Can GBS cause preterm birth, stillbirth and late miscarriage? And should I take long-term antibiotics?
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.
If you live a long way from the hospital or have a history of very fast labours, then induction is 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 an induction with your obstetrician, because they will vary dependent upon your personal circumstances.
If you need to be induced for obstetric or medical reasons, the recommended intravenous antibiotics should be started as soon as possible once labour has started or waters have broken (naturally or artificially), whichever happens first and should be repeated 4-hourly until delivery, and ideally for at least 4 hours before delivery.
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 do not eliminate the risk; there are significant risks associated with a Caesarean section; and the recommended intravenous antibiotics during labour are both low risk and highly effective.
If you are having a Caesarean section, our medical panel’s recommendations with regard to GBS are as follows:
Elective Caesareans There is no evidence to show intravenous antibiotics are indicated against GBS when a woman known to carry GBS or who previously had has a baby infected with GBS is having an elective Caesarean unless she is in labour or her membranes have ruptured. 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, ideally for at least 4 hours before delivery.
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. 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.
The treatment of the baby for GBS would follow the charity’s normal paediatric recommendations.
There is currently no good evidence that membrane sweeps are harmful in women known to carry GBS. Indeed 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)
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, of course, 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.
The intravenous antibiotics recommended above (see Prevention) for pregnant women during labour through to delivery to protect her unborn baby from GBS infection are safe for breastfeeding mothers, although you should make sure your medical professionals know you intend to breastfeed your baby.
If you develop mastitis or a breast abscess, you should seek medical advice regarding breast-feeding.
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.
Whilst appropriate antibiotics in labour can prevent most cases of early onset GBS infection in newborn babies, these do not prevent the less common late onset GBS infections. Sadly, until a vaccine is available, there are no known ways of preventing late onset GBS infections although everyone should wash their hands properly and dry them properly before handing a baby under 3 months of age (this is good paediatric practice, not GBS specific). As with early-onset GBS infection, the mother carrying GBS late in pregnancy is a recognised risk factor for a baby developing late onset GBS infection and it may be more likely in a baby born prematurely.
Although late onset GBS infections are not common, it is important to be aware of the potential signs and symptoms and, if your baby shows any of these, please take him/her for an urgent medical review. If you have any history of GBS, mention that at the time. With prompt and appropriate treatment, most babies will make a full recovery from their GBS infection.
Warning signs of late-onset GBS infection, including meningitis – may include one or more of the following:
- poor feeding and/or vomiting; and
- impaired consciousness.
Typical symptoms of meningitis in babies, including GBS meningitis (any of these could develop but some may not be present at all) include:
- fever, which may include the hands and feet feeling cold, and/or diarrhoea;
- refusing feeds or vomiting;
- shrill or moaning cry or whimpering;
- dislike of being handled, fretful;
- tense or bulging fontanelle (soft spot on the head);
- involuntary body stiffening or jerking movements;
- floppy body;
- blank, staring or trance-like expression;
- abnormally drowsy, difficult to wake or withdrawn;
- altered breathing patterns;
- turns away from bright lights; and
- pale and/or blotchy skin.
If a baby shows signs consistent with late-onset GBS infection or meningitis, call your doctor immediately. If your doctor isn’t available, go straight to your nearest Paediatric Casualty or Emergency Department. If a baby has late-onset GBS infection or meningitis, early diagnosis and treatment are vital: delay could be fatal.
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.
GBS is not a factor in the decision as to whether you should be vaccinated against swine 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.
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.
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.