Episode 113 - CTG use in labour and birth
Mel:
[0:00] Welcome to the Great Birth Rebellion podcast. I'm your host,
Mel:
[0:03] 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. So today I've invited Kirsten onto the podcast to talk about fetal monitoring labor, which is In short terms, listening to the baby's heart rate while women are in labour. And Kirsten's expertise is in CTG, but I'm also going to grill her on other methods like auscultating with a Doppler. And we're not talking about fetal monitoring pregnancy today because that's a whole other thing as well.
Mel:
[0:46] So Kirsten, can we start? What do you recognise as the usual hospital policies around fetal monitoring in labour?
Kirsten:
[0:57] They are pretty standard all around the world in high-income countries. Step one is that you divide women up into one of two camps. So they're either low risk or they're high risk. And the individual risk criteria that people use vary a little bit from place to place, but they're fairly standard. Women who end up in the low-risk camp are usually monitored with intermittent auscultation and those that end up in the high-risk camp are usually monitored with CTG monitoring.
Mel:
[1:28] An intermittent auscultation is where you would listen for a moment with the Doppler or a CTG monitor and then stop it again. It doesn't go.
Kirsten:
[1:38] Yeah, so the guidelines vary a bit, but usually you're listening for about 60 seconds and you're doing it every 15 to 30 minutes or more often if you're concerned or more often when you've got to the pushing stage of labour. And obviously CTG monitoring involves listening to the fetal heart rate continuously. And that can either be with an external Doppler monitor or an internal fetal spiral electrode that physically attaches to the body through the vagina. And then monitoring what's going on with contractions as well, again, either with an external monitor or an internal uterine pressure catheter, which we don't use a lot in Australia, but they're used more in other places. And that then produces a graph. And you can either just have that print out on paper, or you can turn it into digital data, which means you can move it
Kirsten:
[2:27] places other than just... The birth room, which is then when we get to central monitoring.
Kirsten:
[2:33] Which is where you then project that data in a central part of the maternity service. So it's usually a staff office or something. And it's not just the one woman's data, but every woman who's on a CTG at the time will appear on a big bank of screens somewhere so that people can keep an eye on all of the CTGs. And occasionally some of those systems will also mean that people who are outside of the hospital can access that data. So you'll see obstetricians pulling up CTGs on their mobile phones from home
Kirsten:
[3:03] or from their office, for example. Not all the systems do that, but some will let you. So around about the 1820s, doctors started inventing devices to help them to listen to sounds inside people's bodies. So they invented early versions of stethoscopes, mostly because whacking your ear on someone's chest to listen to their heart or lungs is you know, challenging.
Kirsten:
[3:28] Yeah, so the stethoscope happened and then not long after that, people went, I wonder what happens if you put it on a pregnant woman and started describing that they could hear something that they said sounded like a ticking watch and recognised that, oh, that's actually fetal heart. And it didn't take all that long then for people to invent a sense of what was normal and what was not normal for the fetal heart and to begin to use it during pregnancy and during labour. A lot of the use in the early years was actually, it ties in with property rights and who gets to inherit money and who doesn't and laws around marital infidelity. So people were trying to prove whether a woman was pregnant or not pregnant and how pregnant she was.
Kirsten:
[4:20] So that they could argue that, you know, while Johnny was off at the war, she was getting pregnant to some other bloke. And so it wasn't, you know, the original use of it had very little to do with actually improving outcomes in labor. It was about men trying to access knowledge that previously women had control over. So the woman knew whether she was pregnant or not and could choose whether she was telling the truth about that or not. And fetal heart rate auscultation was a way for men to get that information from women. Very quickly ended up in clinical practice in hospitals.
Kirsten:
[4:59] And, you know, most of these things are a bit of a double-edged sword. It helps to work out whether the baby was alive or dead because we didn't have that information before then. And it was the early days of cesarean section. So, you know, figuring out the most appropriate use of the technologies that were available at the time, which were things like forceps, unsafe cesarean section, or some really brutal operations that basically involved dismembering babies and pulling them out in pieces. You know, if you knew that the baby was definitely dead after.
Kirsten:
[5:33] Five days of labour, then, you know, you could then use that approach to end the labour for people, which was probably safer than cesarean section in 1850, but you wouldn't want to do it if you knew that the baby was alive. So, you know, it had some advantages and gradually we built up this knowledge base around what normal heart sounds sound like. Some are too fast, some are too slow. There are changes in relation to contractions and most of it's just based on clinical practice and observation and the loudest voice in the room writing a book and that kind of stuff. So the evidence base around what particular heart rate patterns mean and don't mean has never been really all that flash, but we were using it anyway before CTGs came along. We then had kind of the technological revolution that happened, particularly around the time of the Second World War. And we start seeing computerisation in its early infancy start to happen. Along the way, we'd invented the ECG. So we were able to record parts electronically. We'd invented the Doppler. And a lot of that was about finding out where the submarines are during war, but it had applications in health as well. And so we had these new tools that we could use and people started applying them in maternity care and started then listening to the fetal heart using Doppler.
Kirsten:
[7:01] Using strain gauges to measure contractions or putting monitoring wires directly onto babies in the uterus and recording the ECG so that you then have a heart rate data.
Kirsten:
[7:12] Contraction data, a machine that can put the two of them together and print them out onto a piece of paper. And therefore we ended up with the cardiotokograph. And so the assumption really early on in the literature is that because you are now monitoring all of the time and not just part of the time, that you're going to stop babies from dying. You're going to stop babies from getting injured from low oxygen levels. Care providers are going to be a whole lot less anxious because they know what's going on the whole time. And so therefore, they're less likely to jump into a cesarean section or an instrumental birth when it's not necessary. So it was expected that this thing was going to be the solution to everything. And so CTG monitoring got introduced into clinical practice really quite quickly after it was invented while people were still figuring out what was what in terms of how best to make use of the information that it generates and how to respond to it. And well before we started evaluating it to know whether it actually delivered
Kirsten:
[8:13] on the promises that people had said that it was going to achieve for us. And as a consequence, we then went and did the evidence, which I'm going to guess that you're going to want me to talk about in a moment, and showed that, in fact.
Kirsten:
[8:26] CGT monitoring is actually not really all that useful, and it's not that much better than intermittent auscultation when it comes to keeping babies well, and it performs worse than intermittent auscultation when it comes to the things that we end up doing to birthing women. But we've got this situation now where it's really, really, really, really, really difficult to back away from the use of the technology because it is so deeply embedded in practice and no one really knows how to be a midwife and how to be an obstetrician without it anymore.
Mel:
[8:57] Because the common ways CTGs are used in hospital is that a woman will come in during labour and then the hospital wants to admit them into the birth unit. A lot of hospitals still do what we call the admission CTG, which is women get strapped onto the CTG just to check everything's okay at the time of presentation. And the thought is, is that that would be taken off and then they would be monitored in a different way. But that's done for any woman, low risk, high risk, and there's no evidence behind the admission CTG.
Kirsten:
[9:31] The only evidence has ever been done in low risk women, because the idea is that, you know, already by the time we were starting to do the admission CTG research, we'd already done a whole pile of research about its use in labour and people had already decided that anyone who had risk factors was going to get monitored continuously. So you don't need an admission CTG, you just have a CTG if you're high risk. So the admission CTG is based on the assumption that if by history alone you can't identify a risk factor for a woman, then the CTG, the admission CTG allows you to identify a fetus that might actually still be at risk in order to then say they'll do better if you put them on a continuous CTG for the rest of their labour. But that requires that continuous CTG monitoring improves outcomes.
Kirsten:
[10:21] And at the time we started doing that research, we already knew that it didn't, but it didn't stop anyone from doing the research. And so not surprisingly, admission CTGs don't improve outcomes because in Shepard and in labour CTGs don't improve outcomes. So we have evidence. The evidence does not prove that it's beneficial. So it's, you know, it's different from saying there's no evidence. We have evidence. The evidence has said it doesn't particularly help. There's one exception to that, which we'll no doubt talk about. I've just been looking at evidence this morning and one of the trials I was looking at was from the 1970s and they had 20-25% of their population were considered to be high risk. Now it's 90%.
Kirsten:
[11:06] So we've got a situation where the stillbirth rate and the neonatal death rate have fallen consistently from the 1960s through till the present time, not so much in the last 20 years, but certainly a lot in the early days. And yet, even though the risk of a poor outcome has fallen, the number of women who are considered to be at risk for a poor outcome has astronomically increased. We're actually really bad at risk assessment.
Mel:
[11:33] Yeah. So what you're saying, Kirsten, is that initial use of a CTG for low-risk women, and we'll learn later for high-risk women, hasn't been shown to have any benefit when they do research it. And then, so then we know really that low-risk women, although the unicorn that they are now in maternity care because everyone manages to adopt a risk label at some point in their pregnancy somehow, there's no place for the use of CTG for low-risk women where there's no concern in their life. Right.
Kirsten:
[12:05] I would actually not say that's correct. And I think now's a good time for us to talk about the evidence. So the things that we've looked at are whether it prevents babies from dying
Kirsten:
[12:14] either during labour or in the week after birth. It doesn't. Whether you're at low risk or high risk, there's no difference in stillbirth rates or neonatal death rates, whether you use CGT monitoring or intermittent auscultations.
Kirsten:
[12:28] CGT monitoring does not save babies' lives. The other thing that people are worried about then is about injury to the baby's brain that happens from low oxygen levels during labour.
Kirsten:
[12:38] And so the things that we look at are whether the baby develops seizures.
Kirsten:
[12:43] Whether the baby develops a condition called hypoxic ischemic encephalopathy, of which seizures are one of the symptoms of that. There's a whole bunch of indirect short-term outcome measures like gas gauze or acid levels in the cord blood, which are not particularly good measures as to whether there's been an injury or not, because there's lots of other things that cause them to change. And then the really important one, of course, is just this baby have cerebral palsy when it's one year or two years old. Is there a permanent brain injury that's going to affect that child forever? So no difference in terms of mortality rates. The cerebral palsy rate, there's only ever been two studies that have looked at that.
Kirsten:
[13:23] One was the Dublin trial, which is the biggest of the CTG trials, and it was a mixed risk population. So some people were low risk, some people were high risk. And it showed no, that whether you had CTG monitoring or intermittent auscultation made no impact on the cerebral palsy rates in the long term. There's one other trial where all of the women in the trial were in preterm labor between 26 and 32 weeks. And in that trial, if you had CTG monitoring and then were born as a fetus, then your chance of developing cerebral palsy was two and a half times higher than if your mother had had intermittent auspultation during labour. So in preterm labour, intermittent auspultation produces better outcomes than CTG monitoring does. The one area where CTG monitoring is getting better results is reducing neonatal seizures.
Kirsten:
[14:15] So if you use the CTG, the chances of developing neonatal seizures during labour is half that of when you use intermittent oscultation, which sounds like a lot, but when you look at the entire population on which all of the research has been done, we're talking about 15 less seizures per 10,000 women. It's only a small number. You need 662 women to have CTG monochem to prevent one baby from developing neonatal seizures. If you then break it down by risk category, the women who benefited most in terms of seizure prevention are actually low-risk women, and there's no benefit seen in the high-risk population.
Mel:
[14:59] Mm-hmm.
Kirsten:
[15:00] So, when you say there's actually no evidence at all for using it in a low-risk room, that's actually not true because some women who really, really, really want to avoid a baby that has neonatal seizures, they might actually say, look, I'd rather have a CTG monitor during my labour than use intermittent auscultation because the evidence supports that. The trade-off is that they will face a higher chance of cesarean section and instrumental birth as a consequence of using it.
Kirsten:
[15:30] So for that 662 extra women who need to be monitored, there'll be 12 women who have cesarean sections and 17 women who have an instrumental birth, who if they had intermittent auspultation, they wouldn't have had either of those. So, you know, that's 29 more women having a surgical birth to prevent one baby from having seizures. And that's not a decision for me to make as a clinician. That's for the woman to decide, is that a risk balance trade-off that works for her or isn't it? And some women will be much more sensitive towards avoiding surgical birth and others will be more sensitive towards avoiding seizures.
Kirsten:
[16:08] The important thing about the seizure stuff is so that we know that it doesn't translate into long-term outcomes. So the Dublin trial was the one that had the really big impact on seizure rates, much higher seizure rates in intermittent and auscultation. But when they looked at their long-term data, there's no difference in cerebral palsy rates. The opposite happens in that preterm birth trial where they found no difference in neonatal seizures, but this big difference in cerebral palsy. So we've assumed that the two are the same and that one is an early sign for the later disorder, but they're probably not. And because we go around thinking that we know what the evidence says and that the evidence says that ctgs are good for babies brains no one's ever actually gone okay that's interesting what's going on here why why are the kind of seizures that the ctg is preventing not the same as the disorders that we're seeing when those babies are one and two years old there's clearly something else going on here and it's possible that The seizures that are happening early on, it may not be due to low oxygen levels. There might be something else that's causing them.
Mel:
[17:21] Okay. So another thing that is done in hospitals is that anybody who's got a risk factor, they assume that they should just have continuous CTG monitoring. You know, you name it. If there's a risk factor, put a CTG on, which theoretically makes sense. If the clinician is thinking this baby's got more risk of something going on in their labor, it makes sense on a human level to monitor every single little heartbeat that that baby does and to react to any little change from what's considered normal.
Kirsten:
[17:54] It makes sense if you assume that the technology is working. Working. Yeah. Cheating something. Yeah.
Mel:
[18:01] Yeah. So what's the research there then? Is there any research that supports the use of CTG monitoring for women who have risk factors?
Kirsten:
[18:11] The vast majority of that research takes women who've got risk factors and smushes them all in together in a blender. So like the Dublin trial includes preterm women, postterm women, older women, women with diabetes, women with preeclampsia, women with small babies, women with meconium stained licor, women with twins, all in the one group compared to, and then compares CTG use with intermittent auscultation. So it might be that women who are giving birth preterm actually do worse with CTG monitoring, which seems to be the case from this other child that we've.
Kirsten:
[18:51] Seven times better with CTG monitoring. And when you put them both in the same trial as smooshing together, one cancels the other out. And so we can't then unpick, is there a particular population of women where CTG monitoring might actually be of benefit? Because most of the research has this approach where they just smoosh everyone in together. There's only been three what I call single risk trials where they've looked at one individual risk factor, is CTG monitoring better in intermittent hospitalization. One of them is that pre-term birth trial I talked about.
Kirsten:
[19:24] There has been one about VBAC, but it is too small to have been useful. So I've had 50 women in the CTG side of the trial and 50 women in the intermittent hospitalization side of the trial. No babies died. It was underpowered to detect a difference in cesarean section, but the seizure rate was higher with CTG use and any of the outcomes that they measured for babies was no different. But, you know, probably only because the trial was small. So it's really not
Kirsten:
[19:48] a particularly useful trial on its own. The other one has never been published, but it's in the Cochrane Review because they got the data from the research team and it was about meconium stained-like or no difference in any of the outcomes for the baby, whether you used a CTG or intermittent auspultation. Which means that when people come to me and say, well, what about with my twin pregnancy? What about when I'm being induced? What about if we're augmenting labor with oxytocin? What about if you listen to the fetal heart rate with intermittent auscultation and you hear an abnormality? Should you put a CTG on or not? We don't know.
Kirsten:
[20:26] No one's ever actually addressed that in research to know that if you hear something abnormal with an intermittent auscultation, whether that's a doctor or a pinnard, that putting a CTG on is going to help in some way, which is astounding, really. The list just goes on. The answer is we don't know. No one's ever done the research. Because we've predominantly run around going, it works, it works, it works, it works. Let's not actually be honest about the evidence. But here's the kicker. So yes, we know that there's problems with CDG interpretation. If you give CDGs to a bunch of people, then you will get quite a wide range of variability with some people saying they're normal and some people say they're not and, you know, vice versa.
Kirsten:
[21:12] Midwives seem to do better. They're more consistent at CTG interpretation from one person to the next than obstetricians are. And it's not just a lack of knowledge because one of the studies actually took obstetricians who were expert witnesses in legal cases about CTGs and they had a problem with consistency of interpretation as well and not just with consistency from one person to the next but over time so if you gave them the same CTG three months later they sometimes called it a different thing so you'd think then well a computer's going to be consistent and it's going to call it the same thing every time and it does But then when they've applied it in a large population study to see whether that translates to better outcomes, it doesn't. It doesn't improve perinatal outcomes for the baby and it doesn't prevent the rise in cesarean sections that we see with CTG use.
Kirsten:
[22:03] How we went about developing an understanding of the physiological basis for the changes that we're seeing is, again, deeply misogynist and not great. And there's now some physiology researchers are kind of playing catch up with this and are now starting to do research that usually involves doing fairly horrible things to pregnant sheep and discovering that a lot of the things that we thought we knew are actually not factually accurate. So ever since I was a baby medical student, I was taught early decelerations are due to head compression, variable decelerations are due to cord compression.
Kirsten:
[22:42] Late decelerations are due to hypoxia. that's actually all nonsense.
Kirsten:
[22:46] The key is that what you need is you need a particular fetal heart rate pattern that reliably tells the difference between a fetus that has low oxygen levels and is compensating. Because most all of the changes that we see in the heart rate are about babies protecting themselves from when the oxygen level is low, which makes sense. They stop moving quite so much because that burns up a lot of oxygen. They shift blood away from parts of their bodies, like their fingers and their toes that aren't quite as important, and towards their brain and their heart. They slow their heart rate down because hearts need quite a lot of oxygen per heartbeat. And if you can not do that as often, you need less oxygen.
Kirsten:
[23:34] So that stuff's actually part of the baby protecting itself and ensuring that it stays healthy. What we need then is a test that tells us when we go from a baby that has low oxygen levels, but is completely fine and is compensating to a baby that is
Kirsten:
[23:51] no longer compensating and starting to be injured. And we don't have a reliable heart rate pattern that tells the difference between those. And so as a consequence, we end up doing cesarean sections and instrumental births or just yelling at people and cutting episiotomies or whatever to speed the labor to speed the birth of the baby up and most of those babies come out and they're completely fine so it's really like this this i have competing conversations inside my head between kirsten the researcher and kirsten the clinician you know i'm not working clinically anymore but when i was i have to function in a clinical environment that requires you to do the best that you can with the evidence base but as a researcher i know that the evidence base is really, really a problem and most of it we shouldn't be using in clinical practice but we are forced to because of the history of what's happened with fetal monitoring in labour.
Kirsten:
[24:44] Part of the reason that I started this journey was that during my professional lifetime, I have experienced a small number of babies who died in labour despite CTG monitoring. But we can't, you know, pretending what the CTG evidence actually says is not the way to move forwards in terms of improving outcomes. And, you know, if anything, it's stopping us from doing the research that we need to do to try and find some solutions to the problems that we're still seeing.
Mel:
[25:12] So what I'm hearing then, Kirsten, is that we actually haven't done the background basic work of even working out what a normal fetal heart rate is for a baby that's born well. So we don't know that information yet, but we're using CTGs to try and diagnose babies whose heart rates have become abnormal, but we're yet to properly understand what normal is. And so there's, yeah, so there's this overreaction when we see something that we think might be abnormal, And that's what you were saying with women who have a CTG, they have higher rates of cesarean sections and higher rates of instrumental births without a correlating improvement in the condition of the babies, Kirsten's nodding, without a correlating benefit. So we increase interventions without showing that they're beneficial, potentially because practitioners don't really know what's abnormal in a CTG, so they're acting defensively and in a just-in-case kind of way.
Kirsten:
[26:08] Yeah, but it's not just practitioners, it's researchers and physiologists as well. It's not that the evidence is out there and the clinicians are just dumb and we need to send them to a training course. We just don't, no one knows. What we're trying to do is use the baby's heart rate to look at its oxygen levels. If you were really, really short of breath and you went to an emergency department and said, I'm really having trouble breathing. I think my oxygen levels are low. And somebody took your pulse and said, and said, it's fine, go home, you would not call that good care. And yet that's precisely what we do in maternity care. The only test that we're using to try and get some information about oxygen levels during Lani Bar is the heart rate. For a time period, we had a thing called fetal oximetry, where you could actually directly measure the oxygen levels of the fetus. And it did involve broken people's waters, rupturing membranes, putting a device in through the open cervix past the baby so that it rested on its cheek.
Kirsten:
[27:12] And like the finger things that we now use for measuring oxygen levels in adults and babies, it worked on the same principles. And so you could actually measure oxygen levels in the baby. And there was some research done about it. the research was only ever designed to show that if you did a CTG and then added oximity onto the CTG as well as the CTG, that you could reverse the rise in cesarean section rates that you see with CTG use. And the research got to the point where it showed that, in fact, it didn't reverse the rise, but we never stuck with it long enough to know whether it improved outcomes for the babies and we never compared measuring the oxygen levels on their own
Kirsten:
[27:55] with measuring with a recording of CTG. We just gave up on it and I think and again that's because we believe so strongly that CTG monitoring is actually doing something useful we've let go of that but for us to get there we've got to admit that what we're doing now is actually not effective and that's been that's a real barrier to improvement is this running around pretending that what we're doing is actually being effective.
Mel:
[28:19] We're doing all this fetal monitoring to try and stop babies from dying during labour, but also from being disabled due to events from labour. What are the stats here? What are we talking about? How many babies, theoretically, are we trying to stop from, I'm not wording my question very well, but basically what's the...
Kirsten:
[28:37] How often do these outcomes occur, Mel?
Mel:
[28:39] That's what I'm trying to say. How often do these outcomes that we're desperately trying to avoid by using CTGs, how often does this occur in a labour?
Kirsten:
[28:48] So I've used two data sources for this. One comes from the UK from the birthplace study and that's 2011 data and one's Australian, which is 2019, which is the Australian birthplace study. So interpartum stillbirth, so the baby being alive at the start of labour but dying before it's born, affects three fetuses in every 10,000, 0.03%. Death in the first week of life affects three babies in every 10,000. So if you add those two together, then you get perinatal mortality. So we're at six per 10,000. Neonatal seizures is 13 babies in every 10,000.
Mel:
[29:30] Could there be overlap there? Like the babies who were unwell in that first week Oh, sorry, they were the babies.
Kirsten:
[29:36] Yeah, a baby might have had a seizure and then died, so you're counting it twice, yeah. Hypoxic ischemic encephalopathy, so some of those babies have seizures, not all of them do. Some of the babies who have seizures are diagnosed with HIE, not all of them are. That's 18 per 10,000. Cerebral palsy, all up, it's about 20 per 10,000, and somewhere between 3% or 50%, depending on who you read, are due to causes related to labour because some of them happen during the antenatal period and some of them happen after birth. So in the writing, I've assumed that it's 20% of cerebral palsy is due to damage in labour. So that gets us to four babies in every 10,000. So when you then add all of those up, you're looking at outcomes that affect 0.42% of the population. And as you say, That's still an overestimate because some of those babies are going to care more than once in each of those categories. So it still means that if your baby is alive at the start of your labour.
Kirsten:
[30:43] There is a better than 99% chance that it still will be at the end of the labour, even if there is no fetal heart rate monitoring at all. Not that I'm advocating that as an approach, but just to reassure people that birth is actually pretty safe. Really? And let me point out that 90% of women in Australia and most places in the world are being told that they're at high risk for an outcome that affects less than 1% of people. As I said, we're really bad at risk assessment if we have to tell 90% of women that they're at risk for an outcome that happens for less than 1% of people. But think about the ethics of this for a moment. So we're, as I said, very few women are being asked whether this is something that they want. some of them are being strong-armed into having it against their exposed wishes. To have a technology applied, which probably won't increase, improve outcomes for their baby, might make stuff worse for them in terms of the complications that go along with cesarean section and instrumental birth.
Kirsten:
[31:44] And we're doing it to protect our professional reputation. Like in what situation is it ever moral for us to impose an intervention on another human being, which offers them no benefit and possible risk of harm simply in order to protect ourselves.
Mel:
[32:06] Does that not define a lot of what we do as maternity care providers in the system though?
Kirsten:
[32:14] I want to be clear that in saying that, that I'm not blaming clinicians because I think people, I used to hear it when I was in clinical practice and I think people hear that kind of a message and they go, oh, so I, you know, I bust my gut every day turning up at work trying to do the right thing by people and you're telling me I'm doing it all wrong and you don't know what it's like. And I get that because I had that feeling as well when people tell me what I should and shouldn't be doing. The problem is bigger than us as clinicians, because I know as an obstetrician working in a clinical space, I could not say to a woman who's having a VBAC or about to be induced, it's okay, let's not use the CTG because the evidence doesn't support it. You'll be just as safe having intermittent auscultation. As a researcher, I'm confident that's true. As a clinician, I would have lost my job really quickly and ended up being reported to APRA if I tried that. And the reason that those things happen is because of the way our guidelines are structured.
Kirsten:
[33:14] Guidelines aren't evidence-based. And because of these huge gaps that we've got in the research knowledge, we haven't got evidence that we can use to help us practice in ways that actually make sense and will improve outcomes for people. So this is not a clinician's pull your socks off and do a better job or a better
Kirsten:
[33:37] job. This is such a bigger problem. And, you know, we really do need a birth rebellion. We need a feminist revolution of maternity care.
Kirsten:
[33:47] Fetal monitoring is just one aspect of that. When I, in the years leading into the PhD, was looking at things, you know, am I going to do it on water birth? Am I going to do it about GBS? Am I going to do it about CTG monitoring? Maybe it's about vitamin K. Maybe it's, you know, there are so many things that were potential topics. And it felt to me like any one of them would have given me, a key to a lock, to open it and to go, actually, the problem is our beliefs about women and babies and midwives and obstetricians and the way that the world works. And it's about reproducing those misogynist beliefs over and over again in clinical practice in a way that's practically inescapable for us, for clinicians, even if we want to do better.
Mel:
[34:33] So I'm going to summarise what we've currently talked about. And then Kirsten, that is going to very beautifully segue into central fetal monitoring, which is what I want to talk about. So what we've worked out so far is that there's multiple ways that we can be monitoring babies during labor with the idea that this would somehow lead to better outcomes for babies. So there's the pinnards, which is very low tech that the clinician can hear through the woman's belly, what the baby's heart rate's doing. We've got a Doppler where we can listen intermittently to the baby's heartbeat and hear for a minute what it's doing. And that is done roughly every 15 to 30 minutes, depending on the clinical situation, if you need to do more or less. Then we move on to a CTG, which can be used intermittently or continuously. So it would be strapped onto you for the whole entire labor. It's got two big monitors that sit on your belly and they're strapped on. Sometimes those are attached to a big machine.
Mel:
[35:42] Sometimes they are telemetry, which means you can walk around the room with these two things on and they'll beam back messages to the machine magically. Some of them are waterproof and some of them are not. So depending on which hospital you're in, you might be able to use the water if you're on a telemetry CTG. The other thing that we haven't touched on, probably won't go into a lot of detail, is the electronic fetal monitor that can be screwed into the baby's head, which sometimes they will use if a practitioner wants to have the baby continuously monitored.
Mel:
[36:15] And their CTG reading is what they call losing contact, and they can't get a very good printout of the baby's heart rate, they will sometimes screw a monitor into the baby's head, which is thought to more accurately give a printout. And they call it a clip, but it's actually a screw, just in case anybody's wondering if they just sort of peg it on the baby's head. They don't. They screw it into the baby's head. So then... What Kirsten's looked at in her research is what happens to the information that ends up on the CTG? How does that get transmitted around the facility or to clinicians? And there's something called central fetal monitoring. So maybe give us a rundown, a little bit of a rundown of your PhD and research work. What's central fetal monitoring? And then that'll naturally flow into the issues and what you found. Yeah.
Kirsten:
[37:08] Central fetal monitoring takes that data from the woman and the fetus as digital information and sends it to a central location in the maternity service so that somebody can sit at a desk and see the CTG's got all of the women that are currently in labour. The theory behind it is that if you've got lots of people looking at the CTG, then the chance is that any one person is going to misinterpret it and either not notice there's a problem and therefore not take action or say there's a problem when there really isn't one and take inappropriate action will be reduced. And so the thought is that it will prevent overuse of inappropriate interventions, but make sure that the right people are getting care at the right point in time, which is a really seductive idea. But, you know, see the last 60 years of history about CTG monitoring and you'll see that we've tricked ourselves into believing a lot of that stuff for a very long time. So, there's never been a randomised controlled trial about central fetal monitoring. There's three small studies, each of which happened because they were in a hospital where central fetal monitoring had been in use and then it broke.
Kirsten:
[38:23] And they couldn't afford to replace it straight away. So there was then a time period afterwards when it wasn't in use, you know, directly behind this period where it had been. And so that happened in all three of these studies. And so they then compared what was happening for babies before when the CTG, when the central monitoring system and after the central fetal monitoring was in use. And there were no differences in perinatal outcomes for the babies in any of the three studies. And two of them showed that the caesarean section and instrumental birth rates were higher when central monitoring was in use rather than when you had to go into the room to look at the CTG. One of the studies also asked midwives and obstetricians who were working in the hospital, do you spend more or less time in the room now? And they all agreed that since the central monitoring was gone, they actually spent more time in the birth room with the woman, which in itself has implications for safety.
Kirsten:
[39:19] In some places they're used so that one midwife can look after multiple women in labour so that they can you know pull up the ctg for room a while they're in room b and you know dash back if they see that it's abnormal some places have employed in america there's a thing called the perinatal safety nurse and it's their job just to sit at the central monitoring station and keep an eye on all the CTGs so that if they are not staffed for safety, then they can have somebody looking at the CTGs while there's no one in the room with the woman at all in the hope that they can then rustle up some help
Kirsten:
[39:56] at the point in time that the CTG becomes abnormal. So my interest in it actually came from the question of power. And I'm not talking about plugging things into sockets. I'm talking about, you know, power over one another. And I was interested in the idea that central fetal monitoring was not just a way to observe the fetus. It was also a way that people could keep an eye on the midwife.
Kirsten:
[40:23] And the midwife knew that they were being watched, but not when or who was doing the watching. Hospitals are obviously, there are certain social expectations about our conduct as clinicians. And when you combine the idea that somebody might catch you doing something with a set of social rules about how to behave, then it's much more likely that people are going to toe the line. But when it comes to CGG monitoring, as we've seen, you know, that we don't have evidence to suggest that doing this is actually helping people. So I was curious to investigate what was going on in the relationships in between midwives and obstetricians in a place where central fetal monitoring was in use. I knew a place where it had been introduced two years previously, so it was long enough ago that everyone had gotten used to it and all the little settling in hiccups were gone, but not so far ago that there weren't people there who could remember the before times who could tell me about what had changed. And one of the first things that people started saying to me when I arrived was about, oh, you have to look at this thing that's happening. And we call it being K2'd. And so their central fetal monitoring system was called K2 after the brand name.
Kirsten:
[41:34] Being K2'd referred to a situation where the midwife is in the birth room with the woman doing the things that midwives do. The CTG is on. something about that CTG is then recognised by the person at the central monitoring station as not being okay for some reason and they come to the birth room and sometimes that was really disruptive and it would be multiple people and they would literally burst in through doors without knocking without permission and push the midwife out of the way and start taking over or it even included situations which were much more gentle than that, which just, you know, involved going to the door, knocking and waiting for the midwife to come out. But even then, it means that the midwife has to stop what they're doing and go and sort out the person who's at the door, which means they're not doing the things that the midwife's meant to be doing. And so midwives try to protect women's privacy, you know, that the sanctity of the birth space is really important. And it's one of the.
Kirsten:
[42:39] Kind of key aspects of intrapartum care that midwives want to achieve is a safe birth space for women to give birth in, you know, both in terms of physical safety and psychological safety. So in order to try and reduce the chances that people would have particularly this really disruptive entry into birth rooms, they then needed to focus on the CTG and make sure that there was contact the whole time. So we were talking just a moment ago about loss of contact. So that drove the use of fetal spiral electrodes so that people didn't come in just because there were gaps in the heart rate recording. And it meant that they also spent a lot of time writing additional notes on the CTG because then the person out at the outside desk could go, oh yeah, the midwife's seeing that that CTG is not normal and I can see that they're doing stuff. So they're across that. But if the midwife was busy doing the stuff and didn't have time to right.
Kirsten:
[43:35] Then they'd have people coming into the room and taking over. So obviously, that was one hospital and one particular central fetal monitoring system. But as I've gone around presenting preliminary findings of it, I would have midwives in Scotland and Ireland and all in America go, oh my God, that happens at my place too. And so, you know, different brands of fetal monitoring systems in different places were reporting pretty much the same set of behaviours. We had, you know, the disrespectful stuff that we know people perform poorly as clinicians if they're working in an environment where there's lots of disrespectful.
Kirsten:
[44:13] Conversations happening around the place. We've got, you know, people paying a whole lot more attention to the documentation and being worried about the person who's outside the room who may not even be there looking at the CTG and what they're going to say rather than what's really going on inside the room. We've potentially got midwives learning that provided nobody comes to the room, the CTG must be normal because if it wasn't, somebody would have come to my room and therefore delegating responsibility for CTG interpretation to somebody who,
Kirsten:
[44:46] again, might not even be standing outside the room looking at the CTG. So, yeah, lots of stuff that raises safety concerns, which I think is really important given that we haven't actually done research to show that central fetal monitoring is actually a safe option.
Mel:
[45:02] And we don't know what a normal CTG is supposed to even look like?
Kirsten:
[45:08] Yeah, so having more people look at it when we've got this problem that everybody interprets it differently is not necessarily going to help improve outcomes for people. And these things are hugely expensive. There's a whole pile of zeros at the end of the bill for these. And that money doesn't just grow on trees. It comes out of a hospital budget and something else doesn't happen because you're buying a central fetal monitoring system. And that something else might be something that actually improves outcomes, like setting up an MGP and employing more midwives so that women have continuity of care. My mission and why this has become my primary focus now that I'm not in clinical practice anymore is to have people know the truth because there's so much misinformation in maternity care. you know, I.
Kirsten:
[46:05] Almost all the midwives and obstetricians that I talk to don't actually know the evidence. And once, you know, they might have a sense that it doesn't really work. But once you actually start talking to them about the layer upon layer upon layer of nonsense that we've been taught, you know, you kind of, there's this shock and the obstetricians tend not to believe me and think that I'm a nutter.
Kirsten:
[46:26] The midwives often recognize some sense of truth in it and want to go off independently and have a look at the stats themselves. And that's why, you know, I post as much as I can on the website and provide as much of the breakdowns of the detail so that people can fact check and know that I'm not just making stuff up. So I think, yeah, if we get to the point where the two professions, midwifery and obstetrics, can actually recognise that what we're doing is not working, then researchers within those professions suddenly start going, okay, well, what do we do that's better? Or what are the questions that we need to answer so that we can actually fill in some of the gaps and then begin to provide better care? And we won't get there while we keep pretending that what we're doing right now is actually really working very well when it isn't as soon as you scratch the surface and start having a look at it. So I've been running around all over the place in the last couple of months talking about having honest conversations with people and having new conversations with people. And, you know, that needs to happen with women and their families so that, you know, we're not creating this artificial expectation that if you turn up in labour and let us whack this monitor on you, we can promise you that everything's going to be OK because we can't. It means talking amongst ourselves as clinicians, it means having different conversations as researchers, it certainly means redesigning guidelines.
Kirsten:
[47:49] It means having a good serious look at our medico-legal system because we've got people ending up in trouble for not using CTG monitoring despite the fact that there's no evidence that using CTG monitoring actually will improve the outcomes in the first place.
Kirsten:
[48:04] Where to for women? Well, we know that one of the few interventions that we have to offer in maternity care that actually reduces the stillbirth rate is midwifery continuity of care.
Kirsten:
[48:17] Admittedly, it's early stillbirths that it makes the difference for, not the ones around the time of labour. But they're the tricky ones that, you know, the obstetricians, we haven't figured out what to do about those, but mid-miners have been quietly working on making that better. In a continuity relationship, you have time to be able to discuss your options. You have time to review the evidence. You have the same person that you've had the conversations with, hopefully being the person who's actually providing you with care in labour. So you don't have to argue the toss all over again. You are more likely to find somebody who actually enables the decision that you have made to be the thing that happens for you during the course of your labour. You're more likely to have somebody who's in tune with the kind of the sixth sense kind of stuff that tells you whether the baby's okay or not that you can't get from a CTG. They're more likely to have skills around use of a pinnards rather than use of a Doppler if that's something that you're interested in. So I think, you know, everything begins with good midwifery continuity of carer relationships from the start and that enables you then to negotiate what you want care to look like.
Mel:
[49:29] Kirsten, has there ever been any research done on what would happen if we just didn't listen to babies? We know that CTGs are not the answer, but do we know what would happen if we just didn't listen to babies? Not really.
Kirsten:
[49:42] There's never been a study that's looked at no fetal heart rate monitoring of any sort versus some kind of fetal heart rate monitoring. So we just don't know.
Mel:
[49:51] And the hard thing is, is now we can't go back and do the trial because it would be considered unethical to withhold an intervention that everyone's using and believes is beneficial.
Kirsten:
[50:02] I think that the solution is not so much to go back and prove or disprove what we're doing work, it's to step off onto the next technology and to find something that we, you know, so we can abandon this if we find something that's not ctg monitoring but achieves the goals that we set out to achieve but didn't with ctg monitoring then then if we can do the research well from starter, knowing what we now know about how to do research well then we're in a position where we can go okay we're going to move to this we're going to stop doing that so.
Mel:
[50:37] We got five minutes kirsten take messages for everybody out there,
Kirsten:
[50:43] All the rebels.
Mel:
[50:45] Or whatever it is you need to say in five minutes.
Kirsten:
[50:49] If somebody's telling you that you've got to have a CTG because it's going to save your baby's life, they're lying to you and they are deliberately trying to coerce you into a particular approach to care for some reason. So know that if that's the message you're receiving, that it's not evidence-based. We definitely know that instrumental birth and cesarean section rates are higher when CTG monitoring is used than when intermittent auscultation is used. And because both of those things have both short and long-term harms both for mothers and for babies you know they're not just simply oh well it's just another way to have a baby that you can actually see that as being a complication of ctg use it's not that it's not that there's babies that are missing out on good care because those women you know if those women don't have a cesarean section because the perinatal outcomes the outcomes for babies are the same with ctg monitoring yeah get across the evidence and communicate make a decision and communicate your decision really clearly and find my wife who will work the journey with you personally because that gives you your best chance of getting the evidence helping support to make a decision and somebody respecting that decision and enacting it so you get the kind of care that you want in labor epic.
Mel:
[52:03] Guys that's a wrap i reckon we've done it yeah mic drop and if you want to learn way more about ctgs and the work that kirsten's doing because she's the expert in this field in the ctg world if you want to know anything kirsten's your woman at birth small talk is her instagram handle
Kirsten:
[52:22] And and.
Mel:
[52:23] Twitter and birthsmalltalk.com is where you put all this information in blog posts and there's if you're on the mailing list you will get a huge collection of research articles that Kirsten's written that we're going to put in there and we will see you in the next episode of The Great Birth Rebellion. To get access to the resources for each podcast episode join the mailing list at melaniethemidwife.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 @melaniethemidwife on socials and the show @thegreatbirthrebellion all the details are in the show notes
This transcript was produced by ai technology and may contain errors.
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