Episode 87 - Group B Strep Testing and Treating
[0:00] Welcome to the Great Birth Rebellion podcast. I'm your host, Dr. Melanie Jackson. I'm a clinical and research midwife with my PhD, and each episode I cast a critical eye over current maternity care practice by grappling with research and historical knowledge to help you get the best out of your pregnancy, birth, and postpartum journey. Hello everyone melanie jackson here with you as always almost every woman will be confronted with the decision around gbs screening or treatment in pregnancy and so this episode offers some information you can use to help make these decisions today we are talking about gbs in pregnancy and how it's managed and so if you don't know what gbs is it's called group b strep And if you're newly pregnant and you're wondering what the heck that is, you will learn everything you need to know on this podcast.
[1:00] But if you're coming to the end of your pregnancy, this will also be super valuable because this is where some of the big decisions have to be made. And I want to put a little disclaimer here at the beginning, because when I posted about GBS on social media recently, there was a lot of people saying, but what if your baby has an infection and what if there's signs of infection and so what I want to say is is well healthy women and babies who don't have signs that they need some kind of medical treatment.
[1:30] So of course if you or your baby are unwell and showing signs of a GBS infection of some kind I would highly recommend getting treatment for that because that's why we have medicine to save us from very severe illness and save us from dying and our babies so I'm in no way suggesting that you withhold from testing or treating yourself or your baby if you're unwell. What we're talking about here is routine treatment for well healthy people where
[2:00] whether or not this treatment and screening is actually necessary on a well healthy population. Let's get into it. Okay so I've made a stack of notes and I've got all my stats ready. Okay so what is GBS? So GBS is group B strep, It's a bacteria and approximately 20% of the female population globally, all over the world, doesn't matter where you look, approximately 20% of women, if swabbed, would be colonized with group B strep in the bottom third of their vagina. It's considered not to be a high vaginal population. More bacteria, it seems to be lower. So 20% are colonized. All of this bacteria that we have on us fulfills a function. And there can be a state of dysbiosis where some are growing faster and more prolifically than others, and that can cause a state of disease.
[2:58] And if bacteria gets in one place, or if bacteria belongs in one place and gets into another, for example, E. coli belongs in your bowel. But if it gets in your urinary tract, it'll give you a urinary tract infection. So there's specific important necessary bacteria for every part of our body. And if it moves from that part to another, it can cause illness. But for the purpose of GBS, 20%, if you sob 20% of the global population, that many women would be colonized.
[3:27] But there's a difference between having a colony of GBS and having a GBS infection. It's considered very common to have GBS and a GBS infection is considered very uncommon.
[3:41] And when a baby passes through your vagina during birth, approximately 50% of the babies who pass through the vaginal canal of a woman who has GBS, approximately half of those babies will also be colonized. So if you swap every single baby that's been born from a mother who's GBS positive, half of those will also be colonized with GBS, but not half of them will be infected. So they don't get sick. It's just identified on them. And when your baby is born out of your vagina, you that's their very first seeding of good bad any bacteria that's in there they get seeded with it that starts off their microbiome and just like breast milk starts off the gut microbiome anyway we'll go into the microbiome another time but basically colonization think of colonization as different to infection what we do have is very inconsistent poor information about gbs the studies are all very, very small and so it's difficult to understand exact stats. So if your baby gets an infection of GBS, there's two types of GBS infections.
[5:01] Something called early onset and that can happen in the first seven days after birth and anything after that's considered late onset. We're not going to talk about late onset GBS because that's a little bit different
[5:12] and it's kind of out of the scope of midwifery. That's more paediatrics. So we're just going to talk about preventing and screening for early onset GBS infections in babies but also women can get an infection from GBS. So that's our scope today. let me first talk about screening screening so the reason gbs is on our radar as midwives is that firstly when you first get all of your pregnancy antenatal blood tests done you'll often also be sent for a urine screen like a midstream urine and if anything grows in there and they sometimes want to treat you sometimes a gbs grows in your urine so this is a question i had a.
[6:00] Big on social media so I am going to talk about GBS in urine not right now but right from the beginning of your pregnancy GBS can be on yours or your care provider's radar if it shows up in this urine screen and the other way it comes up and this is what's happened to me in the past not me personally with my clients is say someone has symptoms of thrush or something vaginal and we decide to get a swab to check what it is so that we can decide on a management plan.
[6:32] They will check and they'll tell you what is growing. And then GBS is one of the ones, if you're pregnant and you go for a low vaginal swab because you've got itching in your vagina or interesting discharge or some kind of change that's being investigated, they will often comment on your GBS status as well. So these are the ways that GBS can be screened for accidentally in pregnancy. So, if you already had an idea that you didn't want to be screened for GBS, you may inadvertently discover if you're GBS positive or negative through some of these screening tests. So, if we look at the.
[7:10] Strategies for GBS screening. There seems to be a bit of an ad hoc sort of do your own thing kind of strategy. Some hospitals do it one way, some states do it one way, depending different services do it some ways. But generally, Australia seems to be more like the US where we're doing what's called universal screening, where basically everyone gets a swab, a low vaginal swab between about 35 and 38 weeks. And the sole purpose of that swab is to discover if you're GBS positive or GBS negative. And it takes 24 to 48 hours to get a conclusive result. So it's a bit of a slow test. You don't sort of dip it in something like a pregnancy test and you find out a few minutes later. It's a slow growing thing. That's in Australia. They kind of just have this bit of a blanket, everybody gets swabbed, everybody gets checked.
[8:05] In the UK, it's very, very different. And interestingly, and we'll talk about this more later, in the UK, they see no increase in illness in babies or deaths in babies from GBS with the way they swab, which is risk-based. And we'll talk about risk-based swabbing as we do here in Australia or the US where we swab everybody and treat most people. So in the UK basically they'll have a risk criteria and if the woman falls into a criteria where she has a risk they will offer her the opportunity to be swabbed.
[8:43] They don't just swab everybody. Risks include things like you know either a history of or pre-term labor. So if a woman comes in in pre-term labor they might say look let's do a GBS swab, find out if you're GBS positive. And then the other thing is preterm babies are basically at more risk of every kind of infection and every kind of illness. So if they can.
[9:04] Treat the woman with four GBS, potentially that baby's at less risk. But again, we'll talk about the stats on if we use antibiotics, does that change anything? If your waters break before you go into labor, really any gestation, and it's been longer than 24 hours, checking for GBS can help prevent infection going upwards to the woman and actually giving her a uterine infection and potentially also for the baby. So that's another risk factor that might be a trigger to have the swab to find out if you're GBS positive. So those are the two ways of swabbing. And so if you're here in Australia, it's very likely that when you hit your third trimester, at some point, usually from 35-ish weeks, your care provider will start talking to you about the GBS swab.
[9:50] And then other people were asking me on social media, what's the risk of having the swab? There's actually not a particular risk to being swabbed. So there's no danger to having the actual test. So this particular research was done on women who were swabbed between 35 and 37 weeks. Of the women who were GBS positive, then they're all swabbed again at birth. So at the time of labor, if they had 100% positive women, only 70% of them were still positive at the time of birth and 30% were no longer positive so it is definitely a transient bacteria and the swab is actually pretty accurate so if you get the swab done and it says you've got gbs you really you do have gbs and i've seen practitioners assume that women are positive if they were gbs positive in their previous pregnancy they will actually just assume that you're positive also for this pregnancy so two-thirds.
[10:54] Only two-thirds of women are still positive at the time of giving birth. So one-third are no longer positive at birth. So that gives you some indication of the transient nature of GBS. So we can't assume that if you had GBS last time that you have GBS this time. And so I guess everyone got really interested in GBS screening because there is a risk that if you have GBS that your baby can get a GBS infection after birth in the first seven days. Early onset GBS infection is what we're talking about. So that was the problem. People identified that babies get sick, can get sick from GBS infection. Getting into the typical presentations are lung infections, so a kind of pneumonia, sepsis, which is kind of a full body blood infection, and meningitis, which is in the brain and spinal fluid. Those are the three main manifestations of a GBS infection in a baby. So super frightening. Always definitely need treatment. If your baby is sick with GBS, definitely, definitely treat with antibiotics. Like it's a bacteria.
[12:02] We can solve that problem. You know, things like viruses, a bit more tricky. But we've got antibiotics for GBS infections. So that, yeah, so that's what starts all this idea of let's screen everybody for GBS because when GBS gets in the wrong place, like a baby's lungs, meninges into its blood, it causes infection because it's in the wrong place. So let's have a look at how many babies actually will get sick with GBS. All right, I've got stats here.
[12:31] So, one baby in 2,000 pregnancies will get sick with a GBS infection. 70% of those will fully recover with treatment. 20% will recover with disability. So, this can be more for the babies who potentially suffered really high fevers or had the meningitis. Is that including only full-term babies or is it preterm as well? All babies, every single baby, any risk level, preterm, full term, high risk, low risk. This is every single pregnancy. So they got these stats by looking. And this is not just GBS positive women either. This is, if you look at 2000 pregnancies, one baby will get sick with GBS, regardless of how many of them were positive or negative. And then, so when you sift all of that out, in terms of death rates, babies dying from a GBS infection of all pregnancies, you'd have to have 17,000 pregnant women. One of those babies will die from a GBS infection. So I've got some UK stats here and these UK stats are from when basically there was no universal or no guided management of GBS. They looked at 573,408.
[13:51] Full-term pregnancies, yeah, so over half a million, over half a million pregnant women at full-term. There was 205 early-onset GBS infections.
[14:05] 573448 equals 0.003, and if I times that by 100, that'll give it… Yes, you have to times it by 100 to get a percentage. So 0.04% of babies, of all babies, will get an early onset GBS infection.
[14:24] And that roughly works out to 1 in 17,000 by the looks of it. Also, you go by the other stats. Now, of the 203, sorry, 205 babies who had the infection, 13 of them died. That's the stats. So in that one year in the UK of over half a million births, there was 13 babies who died of a GBS infection. So those are the numbers. And so what they've worked out, I did read one study, 99.85% of babies born to women who carry GBS will be unaffected by death or disability.
[15:09] 99.85% of babies born to women who carry GBS will be unaffected by death or disability and what women need to decide now is how they feel about those numbers and if they're motivating enough to firstly get the GBS swab because there's nothing wrong with getting the GBS swab and finding out if you are GBS positive or negative the decision comes is now what kind of treatment would you like to accept for that if you want to accept any treatment so the assumption from a hospital if you are going through just routine hospital care this is very generalized I know that some services will be different they will want you to have the swab and if you're gbs positive they'll ask you to come in during labor potentially slightly earlier because if you apply the treatment protocol correctly antibiotics needs to be administered four hours before the baby's born, So they may say to you, you're GBS positive, so come in a little bit earlier, or they might not mention that. But so when they had a look at this protocol of timing, so they have done a little bit of study on the timing of the antibiotics.
[16:20] And they did find that antibiotics does reduce colonization. So, in 90% of babies. So you know how I talked about at the beginning that if a woman is colonized with GBS and her baby's born, half of those babies will be also colonized with GBS. Antibiotics reduces colonization by 90%, but it has to be given. It must be given for at least four hours prior to birth. If you give it closer than four hours, they showed a reduction in effectiveness by 50% of the antibiotics. So I remember being a student and seeing this baby crowning, so nearly born, you could see the baby's head. The midwife was frantically trying to get a cannula in to administer antibiotics because the woman was GBS positive and she was telling the woman to not push because she had to give her antibiotics for GBS. They're like we've been at the same birth smell. So, but that's about colonization, but guess what? They haven't found, they found that although antibiotics reduce colonization, it doesn't reduce the stats on illness or death. So fun times, I can't explain that, but that's what the research says. Basically, there's a lot of wriggle room. So you've got a decision to make about whether or not you want to be swapped.
[17:44] Some services are very coercive and abusive and will say things to women like, if you don't have this swab, I'm going to report you to family services or docs here in Australia. The other thing I've seen happening. Your baby may die. Because, yes, they'll say if you don't have this, your baby could die. Yes, it's very possible that your baby could die. One in 17,000 babies do die of TBS. And the other thing that can happen to women is sometimes if you don't submit to the tests that your service is recommending, and this can happen a lot with very boutique services like public home birth programs.
[18:27] Continuity home delivery programs, where actually they're being so heavily watched that if women don't comply to
[18:34] the very strict rules of being on that program, they can boot women off. And so sometimes women are at risk if they decline a test, and it's incredibly coercive, but it's the reality is if they decline a test, they might not actually be able to use that service. So I've heard stories of women being on these programs and submitting to the testing. And as you said, it's a self-swab. So you go on into the bathroom to do your swab. But okay, here's my top. Okay. This is what I've heard. I don't recommend it. Obviously, I'm not allowed to recommend such things. But I've heard stories of women who go into the bathroom and just because the swab would come out of a container and then you put it in another container.
[19:22] So then you just bypass your vagina. It doesn't have to go into your vagina. And then they just send it off to be tested, unaware that the woman didn't actually do the swab. So don't swab a wall or a toilet or anything because that'll grow something funky. But I'm just saying what I've heard is for women who know that if they don't do this test, they're going to get removed from their service that they've been in as a result of declining this test, there are ways around it because they do trust that you've done the test.
[19:53] So, so far we've covered that there's two types of screening options. You can either have universal or risk-based. Here in Australia, it's universal. You can also accidentally be swabbed or tested for GBS in your urine or any regular vaginal swab that you have through your pregnancy. And the reason that we're swabbing is because some babies do get sick. One in 2,000 get sick. One in 17,000 die from a GBS infection. So then when you think about those numbers, I guess the question that gets asked is, if all of this can save just one life, wouldn't that actually be worth it? Wouldn't it be worth screening all these people and finding out who's got GBS if we can prevent one baby from dying? So we'll take this chance now to talk about the treatment that's offered to women who are GBS positive in pregnancy. So if you present to your facility, hospital, wherever you're giving birth, or if you're having a home birth, it'll be different.
[20:53] But if you're GBS positive, you'll be offered an IV cannula, which stays in your arm through the duration of your labor. And every four hours, you'll be given IV antibiotics through that cannula. So that's straight into your blood. And the thought behind this is that if GBS is a bacteria and we can reduce the numbers, then we can reduce the infections on babies. So the numbers then on treating. So we need to give, this is UK stats, but this is what we've got. You need to give 1,191 women antibiotics in labour to prevent one case of GBS infection. You need to swab 5,704 women in order to get the result that's going to lead to one less baby getting GBS infection. So the numbers needed to treat is quite large. So we need to unnecessarily give 1,191 women antibiotics to prevent one baby from getting sick.
[21:59] So why wouldn't we do that? What's the issue with giving, you know, 20% of the population antibiotics during labour? There's a few issues, I suppose. Firstly, in order to be effective, they need to be done four hours prior to the birth. So you actually need to be in the hospital for a length of time. And one of the things that we know about birth is that the later you go to hospital, the less intervention you're going to have and the higher your rates are of having a vaginal birth with less medical intervention or interruption in your birth process. So women are routinely told by midwives, only come in when you're in established, strong, regular labour. Don't come in too early. So the issue is, is if we really do want to treat GBS with the protocol that does reduce colonisation, then you need to go into hospital earlier.
[22:52] And we know that's problematic already. Then antibiotics are an amazing invention. But the issue is, is that we're gradually and steadily building antibiotic resistant bacteria. So there's a time limit on how long us as a civilization can continue to use antibiotics in a way that they're going to actually be effective. Because we are breeding superbugs and bugs that will not be killed by antibiotics. So that's the issue is that the overuse of antibiotics doesn't, you know, actually encourages the growth of antibiotic resistant bugs. Now, I'm not saying if you're sick, if you go into your labor, you know, you're GBS positive, you've got a fever yourself. Your waters have been broken for longer than 24 hours and your baby's showing alterations in their heart rate. That's a really good reason to suspect infection and to accept antibiotics. That's when we need antibiotics for treating sickness the issue with gbs is that we're treating well healthy women and well healthy babies with a medication that already has a short shelf life in the grand scheme of our humanity and our you know our lives because there's antibiotic resistance but also when you give somebody antibiotics it wipes out a percentage of that good bacteria and the bacteria that we need for our bodies to function properly.
[24:20] And we will have a whole episode on the microbiome because it is linked to things like immune system, brain function, childhood development, allergies, the epigenetic function of our bodies. Like it's really deep. So we're not going to go too far into the microbiome except to say, do you want to start the life in your parenting and the life of your baby through a vaginal canal that's had an antibiotic treatment potentially unnecessarily because that's your baby's first colonizing event. That's where they start to build their microbiome is what they collect from the vaginal passageway as they're born.
[25:03] So the big argument, and I'll put all these papers in their folder for those who are on the mailing list, the big argument that the UK came up with for not doing these routine swabs and routine antibiotics for anybody is they have serious concerns about the impact on women's and baby's microbiome because of this overuse of antibiotics. So we need to know what is it doing to us as a population when you're giving one-fifth of all humans antibiotics at the point of birth. And now it's up to women then and their families. So this is the feedback that, you know, that some people kindly received.
[25:44] Offered on Instagram is well that's no comfort to the baby who died or the family who lost their baby or you know of course it's no absolutely no comfort of course it's not because it's a terrible situation and caring for a baby who's sick in neonatal intensive care is just a horrific experience I know I've witnessed it intimately with family members I know what we're saying is is will that, do those numbers make you want to get a GBS test and antibiotics? If you've heard those stats today and you think I absolutely want to get a swab
[26:26] and I absolutely want to get antibiotics, totally fine because you've got the information now. But then you might also think those numbers don't feel frightening enough for me. Those numbers don't feel frightening enough for me to feel like I need to get a GBS swab and be treated by antibiotics. So that's completely your choice. I'm not telling you what to do. I'm just saying this is the info. And you can ask your care provider what their policy is and hospitals can print off the policy and that has all of that detail. You know, if this, then this happens.
[26:58] So not only is there a risk to the microbiome of both the woman and the baby, there's also a very, very small risk. This is small and And this is why we don't do antibiotics at home, basically, because as Bea, you were saying, if a client of mine is GBS positive, has decided to have the swab, I do let them know that if you're GBS positive, we don't do IV antibiotics at home because there's a very small risk of maternal anaphylaxis. So a severe reaction to the antibiotics where you get anaphylactic and literally your throat starts to close up, you know, so that's small risk.
[27:33] We already spoke about antibiotic resistance and the impact on the microbiome, but there's also some research about how if you wipe out part of the microbiome with antibiotics and you create this dysbiosis and imbalance.
[27:48] Then you open the body up to what we call opportunistic colonization by a pathogenic, like a bad bug, essentially, like E. Coli, an overgrowth of things like candida which is thrush and women can get it on their nipples and the baby then gets thrush and all these things so it's a horrible experience to experience thrush especially if you didn't need to because you have antibiotics as a preventative rather than actual treatment so those are some of the risks of having antibiotics there's also the you know the potential risks of having a cannula again that's just isolated to the cannula but it contributes is to this over-medicalization of childbirth, which really is midwives. And from the literature, we're trying to move away from medicalizing childbirth so heavily. But the research on this, and this is based on the Cochrane Database of Systematic Reviews. So as we heard in episode 4, Cochrane Database of Systematic Reviews is considered the most scientific publication. They have concluded that GBS swabbing, screening, universal GBS screening of everybody, it doesn't have enough evidence to support its use. The other thing they have found is that they cannot recommend routine antibiotic testing.
[29:11] Administration to every single GBS positive woman because the level of evidence is very very poor on its effectiveness yes because what Cochrane does is it pulls all the studies and looks at all the stats and decides whether or not the research is good enough quality to make conclusions so they basically said it looks like maybe antibiotics can reduce colonization and maybe sickness of babies but we can't really tell because the studies are small and they're not very good quality. So at the moment, Cochrane has not been able to confidently recommend the use of antibiotics for the problem of GBS infections. And it also doesn't have enough research and information to recommend that everybody get a GBS swab. Certainly a risk-based approach seems to be an option where you actually just
[29:59] look at the individual and decide if the swab is appropriate for them. And the other thing that people are asking too is, well, what if I decline all of that and my baby does get sick with GBS. Well, we saw the stats, one in 2000 will. As I said, it's a bacteria, so the baby would be treated with antibiotics and only approximately, if you didn't know you had GBS or you declined the testing or declined the antibiotics and your baby still gets unwell.
[30:30] They can be treated with antibiotics. So we're yet to be able to fully work out how much if even if antibiotics is the solution to the problem of GBS. There's no doubt there's a problem of GBS because one in 2,000 babies get sick and one in 17,000 babies die. So it's a problem that needs attention. The problem is that we've, and this is what Cochrane identified.
[30:56] Was that because we've gone so far down the antibiotic rabbit hole and this has become standard treatment, is that we can no longer ethically study any other way of managing GBS because it's considered withholding treatment and that would never get through an ethics committee. So there is some thought that actually the opportunity to study alternative management of GBS colonised women is gone. And so there's a concern amongst the scientific society that we actually will never be able to explore other options for GBS because the use of antibiotics has become so accepted as a treatment even though it's not evidence-based. The other thing that comes up for women is if you've got GBS in your urine, that can be a red flag for your care provider. Now, what's that about? So there's basically two types of urinary tract infections, and there's those that are asymptomatic. So you have a bacteria in your urine, but you don't have any symptoms of a urinary tract infection, in which case you don't have an infection. You've just got colonization.
[32:04] And then there's, if you've got an actual UTI and then you get your urine checked and they grow the bacteria that's in your urine, and then they tell you then that your urinary tract infection is a result of GBS. What do you do about that? And so there is actually a few studies on this and I will put them in the folder as well for you to have a look at. So basically when they check you for a urinary tract infection or they check your urine, They check how many parts per million or per 10,000, I think, for –.
[32:36] Urine. Anyway, I'm not sure of the exact details. So then you can either have a low concentration of bacteria or a high concentration of bacteria, which is probably what I was trying to say. And there's been studies that have been done to check if a high concentration of GBS bacteria in your urine correlates to also having a high GBS count in your vagina. And so the current research suggests that a high count in your urine can also indicate that there's a high count in your vagina so they will immediately just assume that if you've got a high count of gbs in your urine that you also have a high count in your vagina and will seek to offer treatment with antibiotics now if you do actually have a symptomatic urinary tract infection i would highly recommend getting some kind of treatment for that because what they've found is for women who've got gbs in their urine just like any other urinary tract infection it can pull you at risk of preterm birth however you want to treat it naturally with antibiotics or however you want to do it I've had clients with high GBS in their urine with also symptoms who've declined antibiotics and used a range of other alternative therapies to manage that that's obviously something that those women have pursued and used themselves so for women who are wondering why if I have GBS in my urine have I just been assumed to have GBS in my vagina.
[34:00] It's because there has been a noted correlation. However, if there's low amounts in your urine, the correlation is a lot less. So it's less accurate if you've got low GBS in your urine to assume that you've also got it in your vagina. So absolutely, yes, the question I've had was, should I treat GBS if it's in my urine?
[34:24] Personally if it's asymptomatic and you only found the gps because you accidentally found it when you were doing a routine urine test then i don't think that you need antibiotics because, at any one time our body is working on getting rid of bacteria from places it shouldn't be and the only time that your body's not coping with that process is when it's obviously sick so if you have a uti your body's not been able to get on top of that infection and it's struggling and it's telling you it needs help. So get help, of course, if you have symptoms, but if you don't have symptoms, you've got a whole lot of other options for managing GBS in your urine.
[35:03] Thank you for listening to this episode about GBS. To get access to the resources for each podcast episode, join the mailing list at melanithemidwife.com and to support the work of this podcast, wear the rebellion in the form of clothing and other merch at thegreatbirthrebellion.com. Follow me, Mel, at Melody the Midwife on socials and the show at The Great Birth Rebellion. All the details are in the show notes.
This transcript was produced by ai technology and may contain errors.
©2025 Melanie The Midwife
