Episode 112 - Is CTG in pregnancy beneficial?
Mel:
[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. Welcome to today's episode of the Great Birth Rebellion podcast. Today, I've invited Dr. Kirsten Small, who is a career academic, retired obstetrician and an industry expert in the use of CTG, fetal heart rate monitoring. Kirsten's PhD is on the topic of CTG and she is the mistress and owner of birthsmalltalk.com where she offers free and evidence-based information about the use and misuse of CTG monitoring. And we've got Kirsten with us for the next two episodes, but today we're specifically talking about the use of CTG in pregnancy. So if you've ever presented to your care provider in pregnancy and been offered a CTG that you weren't convinced you needed, then this is the episode for you. Welcome Kirsten.
Kirsten:
[1:10] Hello, nice to be back again.
Mel:
[1:13] So whenever I have a question about CTG, I ask Kirsten. So I wanted to ask about CTG in pregnancy, but before we do any of that, for new players, can you briefly explain what CTG is?
Kirsten:
[1:29] Like the good researchers we are, we will start by defining our terms. So CTG stands for cardio, toco, graph. So cardio refers to the fact that you're recording the fetal heart rate. Toco is the Latin word that means contraction. So it records the activity from the woman's uterus. And it's a graph because both of those sets of information are then plotted onto a screen or a piece of paper over time so that you get a graphical recording of how the heart rate changes and how uterine activity changes over time. So you can tell how the heart rate changes in relation to any uterine activity. The uterus bit's a bit more important for labour, but it still has some relevance when we're using it in the antenatal period.
Kirsten:
[2:21] The alternative to it, in labour, the answer to this question is much more straightforward because in labour, the alternative is a thing called intermittent auscultation, where instead of having the CTG machine on the entire time, you listen from time to time with some kind of a device, most commonly a handheld doctor to listen for, say, a minute, and then you don't listen for another 10 minutes or 15 minutes or so. So if we're talking about pregnancy, it's a bit trickier because we don't use CTGs continuously. They're done for 20 or 30 minutes until people decide that they've got enough information to decide how to interpret it. And the alternatives are much more broad ranging. So it might be intermittent auscultation. It might be not to do any other form of fetal heart rate monitoring. It might be ultrasound or a blood test or movement monitoring or a combination of all of those things. So it makes the research trickier and it makes the conversation a bit trickier.
Mel:
[3:25] So the CTG, for anybody who's never seen it, it's got these two big discs. What would they be? About the size of a tennis ball? They're flat. Discs. And they would use the one down on the baby's heart rate and the one up on the top of your uterus to see if you've got any contractions. And then they strap them on and you've got to lie down and be a bit still because they're a bit finicky about keeping contact on your skin and getting access to all that information that they're trying to collect. So if somebody says, can we do a CTG? That usually means they're going to collect information about the baby's heart rate, as Kirsten said, about the activity of your uterus, but that they'll need you to probably lie semi-recumbent, expose your belly, have these two things on, and that it'll stay on until they're satisfied.
Kirsten:
[4:12] And the heart rate one requires the lovely blue, squishy, cold ultrasound gel as well to make contact so that it works properly.
Mel:
[4:21] Correct. So that's what you're in for. So great. Now we know what CTG is. I want to give you a scenario here because this is something that I've encountered with my clients. For people who don't already know, I'm a private midwife, so I don't carry a CTG around with me. It's quite a big apparatus. But occasionally I have cause to send my clients into hospital to have an assessment during their pregnancy with the hospital. And our local hospital has this unit, they call it the WOW, the Women's Antinatal Assessment Unit, and basically for any pregnant woman in the area, they can go down there. It's almost like an emergency room for pregnant women. And so I had to send a client there for something. It was not too major, but I couldn't do it. She needed to get a high cervix swab. The low swab didn't show anything, but there's still something going on. Let's get a high vaginal swab. So off she went into there. It took her four hours to get through the unit because they insisted on, before doing anything, they insisted on a CTG.
Mel:
[5:31] Then they did the procedure. Then they wanted to do another CTG afterwards, almost like a benchmark for how was this woman and baby when they arrived and how were they when we discharged them from this fairly minor procedure. It's no more serious than a pap smear and it doesn't take any longer than that.
Kirsten:
[5:53] It's completely unrelated to the presence of risk for the fetus.
Mel:
[5:58] Exactly. She had no, and I had no concerns for the baby. All I knew was is that I couldn't do this procedure for her because we didn't have the equipment. And so this was the best option. And so it just got me thinking why are we doing these antenatal ctgs and i assume that any woman who turns up to hospital during pregnancy with some kind of concern whether it's with the baby or not that they're going to receive an antenatal ctg so can you talk us through why maybe that would be offered
Kirsten:
[6:33] There is a really strong belief that CTG monitoring works, that it tells you whether the baby's happy, for want of a better word, whether they're well oxygenated. It's considered to predict the future. If it's normal now, that means that things will probably continue to be normal for a period of time. It's meant to prevent stillbirth. It's meant to help you to decide who needs induction of labour or who needs caesarean section in order to achieve the birth of a baby that stays well and therefore avoids complications of babies who develop seizures or cerebral palsy or who die in the postnatal period because they were very sick.
Kirsten:
[7:19] And as we're about to dive into it, while those beliefs are very, very strongly held in our healthcare systems and in our legal systems as well, that's not quite what the research says.
Kirsten:
[7:34] And most maternity providers either don't know what the research says or they work in large systems and organisations, where they have to practise in a particular way because the guidelines say so. So even though they know that what they're doing is not based on evidence, They don't really have much choice other than to do the things that they end up doing. That's kind of in a nutshell how we got to where we got to with CTG use. And people think it keeps them safe legally or safe about complaints about not having done a good job or been thorough enough. And because women who are seeking maternity care believe the stories that they're being told, they often feel reassured by the fact that they did everything. They even did a heart rate trace and they said it was normal.
Mel:
[8:27] And so then in the context of an eating natal assessment, is there any research about the benefit or the risks of that or does it give us any information?
Kirsten:
[8:38] There is some research. It's old and it's low-quality research and it doesn't really relate to the way in which we are now using CTGs in the antenatal period. So the research was done between 1982 and 1985.
Mel:
[8:58] So I was born in 84 and I've just turned 40. So we've got research that's about 40 years old
Kirsten:
[9:08] And I was in high school and at lunchtime, we'd sit around and debate whether the Bay City Rollers or ABBA were the better rock group to follow. So yeah, it gives you a little clue about the fact that the world has moved on a little bit since then. There's only been four trials. Each of them was quite small in size, between 300 and 500 odd people. And if you smoosh them all together, we've got 1,627 women who were in the research. Now, that sounds like a lot, but by way of comparison, if we look at the number of women involved in the trials where we've looked at CTG use in labour, it was 33,000. And in that group, they're saying we still don't have big enough numbers of people in the trials to really know for sure what's going on. So we really don't have enough women who've contributed to the research to know what's going on. The majority of the women were in hospital. They were admitted to hospital for observation. And the reasons that they were considered eligible to be in the research are not the same as the way that we do, you know, recommend CTG monitoring. They certainly weren't doing it for well women who just happened to pop by for a vaginal swab to be done.
Kirsten:
[10:27] Only one of the trials was using it for reduced fetal movements. And that wasn't like, that was one of many reasons they were using it. It's not like there was a trial that was specifically about women with reduced fetal movements. None of the trials have looked at reduced fetal movements. Only one of them looked at using it for post-dates. Mostly for things like hypertension, recurrent episodes of bleeding, when you suspect the baby's small, bearing in mind the quality of ultrasound scanning was quite different. So most of that was based on feeling a woman's tummy and deciding that it felt like a wee baby rather than the kind of measures we do now to determine whether a baby's small or not. Going back to that question of what do you compare it with, Do you compare it against intermittent auscultation or not listening to the baby's heart rate at all? What three of the four trials did was everyone actually got a CTG done, but half of the group, the CTG got taken off the machine, folded up neatly, put in an envelope and tucked away where no one was allowed to look at it until after the baby was born. And the other half, the CTG was given to the team that were looking after the woman's care, and they were allowed to use that information to make decisions about how to provide care from that point on.
Kirsten:
[11:50] Which I kind of, like I know how maternity services work, and you have to have a certain degree of expertise in order to put a CTG on and decide when it's finished enough to take it off. So like you don't do that unless you know how to interpret a CTG. So to sit there and look at a CTG and then just stick it in an envelope and not tell anyone about it. I really don't quite know how that went down and whether there was some breach of the protocol with the people going, you need to come and look at this.
Mel:
[12:26] You're suggesting that during the research process that if a sinister CTG was identified by the clinician who had put it on and who was responsible for putting it in the envelope to tuck it away, that ethically they could possibly not bring themselves to not report a pathological CTG throughout the study. Yeah, right.
Kirsten:
[12:49] Yeah. And maybe even if they didn't actually unblind the team, they might've just kind of said some key words that were designed to trigger a different response, which is part of the reason why the Cochrane Review relates this research as low quality because there's no way to be sure that the two groups were actually.
Kirsten:
[13:09] Quite different in terms of what went on with the way people were managed and therefore the results that we see are a consequence of the decision to look at the CTG or to not look at the CTG. The main outcome that I'm most interested in is about deaths. So did this actually prevent stillbirth or neonatal death? And the Cochrane Review only looks at perinatal mortality when you combine the two together, so still birth plus neonatal deaths. It's kind of interesting looking at the Cochrane review, because if you look at all of the deaths, in the group where the CTG was shown to people and allowed to be used for decision-making, the death rate for those babies was 23 per 1,000. When the CTG was not shown to people, it was 11 per 1,000. So it was just a smidge over twice as high. But because the size of the trials is small, the numbers aren't very big, it just fails to reach statistical significance. So strictly speaking, it is not a statistically significant difference in the mortality rate, but the mortality rate was twice as high when people had actually looked at the CTG than when they didn't.
Mel:
[14:31] Not highly powered enough, but the early suggestions seem to indicate that
Kirsten:
[14:38] That CTG use is possibly harmful. Yes. And then when you look at the individual papers, a lot of the reasons that the babies died, there were things that no matter how hard you tried, you wouldn't be able to prevent it by using CTG. So for example, I've just pulled up the paper by Lumley. And there are things like the woman ruptured her membranes at 30 weeks and developed a severe infection. The baby was born at 26 weeks after recurrent bleeding from a placenta previa and died because of lung immaturity. So, you know, a CTG isn't going to make a difference in those situations. A baby was born at 32 weeks after preterm labour and developed a bleed inside its brain because it was premature. CTG monitoring isn't going to fix that. So if you go through and you pull out the ones where the deaths have nothing really to do with CTG monitoring and the Cochrane Review of this does that, then what we end up with is the preventable deaths in theory.
Kirsten:
[15:52] And again, we've got 17 per 1,000 in the group where people were able to look at the CTG and six per 1,000 in the group with the intermittent auscultation. So we're seeing the same pattern. And it actually gets a bit stronger because now it's two and a half times more likely that there'll be a death when the CTG results are looked at. But once again, just fails to reach statistical significance.
Kirsten:
[16:16] None of the other outcomes are statistically significant. So gestational age at birth, admission to the nursery, APGAR scores.
Kirsten:
[16:27] Seizures, caesarean section rates, instrumental birth rates, induction of labour rates, no differences across the two groups. So the only one where it gets close is that death rate. So it's hardly a screaming set of evidence that says CTG monitoring is a really good idea and we should be doing it left, right and centre because we are now doing it left, right and centre. So, for example, if you present saying, look, my baby's not moving very much, you'll have the CTG on before you take two deep breaths. We have never done a randomised control trial that's exclusively taken women with reduced fetal movements and have gone, will a CTG make things better if we do it for you or not? And that group of women, as I said, they haven't even been included in amongst all of the other women that were there who had hypertension and diabetes and bleeding and all of the other reasons that the CTGs were doing. And yet that's probably the biggest group of women that I see CTG monitoring being used in the antenatal period for and with a great deal of faith that doing this will tell you that things are fine. And it concerns me that women turn up with anxieties about fetal well-being based on the fact that their baby's quiet and they just have a feeling that something's not quite right.
Kirsten:
[17:57] Somebody then applies this technology, which not only is not helpful, but might actually increase their risk of stillbirth without telling them that. And then when the heart rate appears normal, kind of dismissively pats the woman on the head and says, there, there, sweetheart. It was normal all along. You just were imagining things and sends the woman off. So she then goes, oh, okay, so I can't trust my instincts about whether this baby's okay or not because the machine says everything's fine and I got it wrong. So if she continues to have concerns... Well, many women will still go back, but I reckon some will go, oh no, they'll just put that thing on again and it'll be all okay and it'll just be a wasted trip to the hospital and no one will take me seriously. And that really seriously bothers me that we're not telling people about the shortcomings of CTG monitoring and the fact that it won't actually tell you the information that you are looking for here. We need to do some other form of assessment before we can decide whether things are okay or not okay.
Mel:
[19:10] I'm just getting my head around this. Are you saying there's one single collective research paper?
Kirsten:
[19:17] One Cochrane Review, and there are four papers in it that have looked at antenatal CTG use, of which three were the, everyone got a CTG and some of them had it hidden in an envelope and some of them didn't. And the other one, it's really not clear what went on, what happened with the control group. There's quite a lot of information about how the CTGs were done, but we're not actually given any information about what was the standard of care when they weren't allocated to the CTG monitoring group. So, presumably, they just got nothing.
Mel:
[19:53] Right. So, one systematic Cochrane Review, which was released in...
Kirsten:
[19:58] The Cochrane Review was 2015, but the most recent research was 1985.
Mel:
[20:06] So, there was still reporting on research that was done in the 1980s.
Kirsten:
[20:12] And there's been no, there has never been another trial about antenatal monitoring since 1985. Now, there would have been time.
Mel:
[20:26] There would have been 40 years of time. We had my entire lifetime to do this research. Okay, so just, I'm summarizing that for everybody. There is one Cochrane Review which has brought together all of the research on antenatal CTG use. The total number of people who were in that study across the four studies was around 1,670-something. The quality of the studies was poor, and none of them included reduced fetal movements as a reason for doing the CTG. But now, if you have reduced fetal movements and you go into hospital, their routine practice is to put the CTG on. And if anything, the research that the Cochrane Review reported on from 40 years ago indicates that there is possibly an increased chance that the CTG will make worse outcomes if it's applied and looked at by your care provider. Do we have any understanding of why the outcomes would have been worse if the CTG was looked at? Why did those women experience more poor outcomes?
Kirsten:
[21:39] No, and it's not really well fleshed out in the studies. The first instinct is to go, well, maybe there were more inductions and more caesarean sections. And so they were delivering babies who were not ready to be born yet, who didn't cope well with labour and ended up dying from complications relating to prematurity. But that doesn't seem to be the case because, and again, it might because the numbers are small, but there was no difference in caesarean sections or in instrumental births or admissions to the nursery or any of those things, or in the gestational age at which the babies in the two groups were born. So we don't really know what the reason is, but presumably different decisions are being made on the basis of the CTG monitoring, and those decisions are the thing that increases risk to the fetus or baby.
Mel:
[22:35] And as you alluded to before, that possibly if a woman has had confirmation by a machine that everything is okay, I'm saying okay in adverted commas, then maybe she'd be more inclined to not listen to her own instinct that something is wrong.
Kirsten:
[22:54] And likewise, given that these were women who were typically in hospital for concerns about themselves and their baby, maybe it's also providing false reassurance for their care provider to go, oh, look, it's okay, we can wait another couple of days. And do it again. And instead of, if the CTG machine didn't exist and every other instinct was saying, no, no, we really need to get this baby out, maybe they're overriding that by having the CTG information added into the picture and therefore sitting tight when in fact, maybe having got the baby out a few days earlier might've been the better idea at the time.
Mel:
[23:34] And I've heard people say things to women like, this CTG will tell you that your baby is okay over the next 24 hours, but we can't promise anything more after that. I've witnessed women who had to go in daily for CTGs because their pregnancy was, again, in inverted commas, high risk. And so one of the strategies is, oh, that's okay. Let's just do daily CTGs because the result of this will last 24 hours. If your baby is okay at the time of CTG, you can expect that over the next 24 hours, it will still be okay. Have you ever heard that argument?
Kirsten:
[24:09] I have, and it's based on completely no evidence whatsoever. Across those trials, some of them were doing them fortnightly, weekly, daily. There's been no research that systematically set out to say what's the safest period in between one CTG and the next, because we haven't even identified that it's actually a safe thing to do in the first place. But there's no research evidence to back up the idea that a daily CTG is better than a weekly CTG or that a weekly CTG is worse than a daily CTG. We just don't know.
Mel:
[24:50] So the only thing we do know is that the heart rate gets picked up and recorded on this piece of paper.
Kirsten:
[24:55] We know that at the time that the CTG is done, the baby is alive. And that's really about all that we're told. The other flip side of this story is about, well, how do you decide that the CTG recording is normal or not normal? And here in Australia, Mel, we have a thing called the intrapartum fetal surveillance guideline that's produced by RANSCOG. Do we have an antinatal guideline?
Mel:
[25:22] Oh, there's no antinatal guideline.
Kirsten:
[25:24] No, no, there is no agreed Australian standard on how to interpret a CTG that's done before labour starts or on what to do in response to an abnormal heart rate pattern. Now, at individual organisation or state-based level, there might be, but there isn't a national standard. And most of the research that's been done about fetal physiology to try and understand what the significance of the wiggly lines are, is done in relation to, labor, where they do some pretty awful things to sheep, I have to say, to produce this research. It's not vegan friendly.
Kirsten:
[26:08] And usually what they do is they clamp and unclamp the umbilical cord to try and reproduce the reduction in blood flow that happens during contractions. So it's a very, it's a completely different set of physiological processes that's going on compared to what's happening in the antenatal period. So people certainly have a system for looking at CTGs and saying they're normal or not, but it's really just, it's made up. It's not based in sound physiological research because the research that started all of this was done on women in labour and then in animal models that are designed to mimic women in labour. And there's not really been any attention to understanding the fetus in the antenatal period and really, really no evidence when it comes to preterm, when the physiological processes that control heart rate are different at earlier gestations than they are at later gestations.
Kirsten:
[27:11] So you begin to scratch underneath the surface of this and you just see that it just evaporates underneath you. There is no solid structure on which we should be building a belief system that if a woman presents with reduced fetal movements, then popping the CTG on is actually a really good thing to do. We just, we don't know at all. And if anything, what little bit of pretty awful old research we've got suggests that it might maybe actually be a bad thing to do. And the fact that in 40 years, No research group have gone, you know what, we really need to sort this out. Let's go and get some funding and do a big trial.
Kirsten:
[27:57] No one's gotten around to doing it. And I think part of the reason is that people are so captured by the idea that what they're doing is right and it works. Why would you upset the apple cart and risk undermining everything that you believe to be true by actually going back and starting again and doing the actual research?
Mel:
[28:17] So what I'm hearing is that we currently don't have any research or an international standard that would tell us what a normal CTG looks like, let alone what an abnormal CTG looks like. It's pretty much up to the institution or the individual clinician to make a decision about that, but they've got nothing other than their clinical experience or workplace policy to go off because there's no actual research.
Kirsten:
[28:47] Right. And the things that we use to decide whether it's normal or not, just being handed down from one generation of clinicians to the next as being, well, that's the way that I was taught and therefore it must be the right thing. They're not grounded in a solid base in research. They're just done that way because that's the way that we've always done it.
Mel:
[29:08] And I think people think in theory, if we can hear the baby's heart rate, that in theory would give us an understanding of the baby's well-being and therefore in theory if the baby was unwell we could intervene because I feel like there'll be people listening going oh but I had a client who had reduced fetal movements and she went to hospital and the CTG was obviously pathological so they immediately went for cesarean section the baby was you know barely hanging on And then fortunately, she got there at that time because if she hadn't have, it could have been a whole different scenario.
Kirsten:
[29:48] But if we lived in a world where no one had invented a CTG and a woman turned up and said, my baby's not moving, what would we do?
Kirsten:
[29:58] And it's not that we would not it's not that we would not necessarily have ended up doing a cesarean section in exactly those same situations and have you know brought this baby out into the world going gee that was close we we're really glad we got that baby out at that time and we do the like since 1985 the world has moved on in terms of ultrasounds we did we didn't do umbilical cord dopplers middle cerebral arteries so the blood vessels in the brain dopplers on babies in 1985 so we've got a whole different range of options that we now have available to us that tell us information about what physiological changes are happening in the baby circulation that might suggest that their oxygen supply is not good and that they're probably better off out where we can actually give them some oxygen or at least some air to breathe. So if we took CTGs out of the picture, it doesn't mean that all women who have concerns are going to be ignored. We will find another way to try and sort out the ones where there really, really is something wrong from the ones where, baby was just having a bit of a sleepy day, without using the CTG as the thing that sits in the middle of it, given that, quite frankly, it's about as effective as giving somebody a rose quartz crystal.
Mel:
[31:22] Well, I mean, the issue is that clinicians have so readily relied on CTG now to give them information of if a woman and baby are well, that I'm wondering if we are confident enough or even have the skill to make an assessment in any other way. I'm a home birth midwife. I've got a Doppler and a Pinard. I could listen to the baby's heart rate. But even then, the research on the use of intermittent auscultation during pregnancy, basically, I ask women, would you like to hear the heartbeat today? And they're like, do I need to? I was like, nope, makes no difference at all. It's just some people like to hear it, but it doesn't make any difference to what?
Kirsten:
[32:04] No, all it tells you is that the baby is alive at that particular moment in time. It doesn't tell you whether it's well or unwell. It doesn't predict the future. And it's kind of become a rite of passage for women to hear the heartbeat at antenatal visits, particularly the first antenatal visit. And so if it's culturally meaningful for people and they want to do it, then great. But it should be considered as a culturally meaningful experience, not as an important healthcare intervention.
Kirsten:
[32:34] There are so many gaps in our knowledge compared to the way that we currently use CTGs and what little research that we have. So, for example, if you have an external cephalic version, if your baby's becoming bum first and they want to turn your baby around so it's head first, they'll do a CTG before the procedure and another one after. Never been assessed in research. We don't know if that's effective or not. Seems like a good idea. Just gave it a crack, became part of standard practice. Don't know. Is it helping? Is it not helping? We do, we have no idea at all. The client you were talking about had both a kind of an admission and a discharge CTG in the sense that as the care started, they were paying attention. And then there's a kind of a, let's just check it's okay for you to leave the building. That kind of discharge CTG idea, never been assessed in research at all to know whether it's okay. And the women who present in early labour, let's just check that the CTG is normal before we send them home to labour at home for a few more hours, never been assessed in research.
Mel:
[33:39] It's all of that arse covering that happens in a sense that they could say if they were questioned later down the track for whatever reason, no, no, the CTG was normal when they arrived and it was normal when they left.
Kirsten:
[33:53] Yes. And unfortunately, the legal system is complicit in this because they too believe the myths that have been taught about antenatal CTG use. And instead of the lawyers going, well, that's nonsense. That's not true. You can't use a CTG to tell you that.
Kirsten:
[34:11] They go, oh yeah, she didn't have a CTG. That's clearly the reason why there was a bad outcome.
Mel:
[34:16] And so I guess the message here too is a lot of clinicians are in a position where they work in a place that requires them to at least offer a CTG according to their policies. So if you're a woman listening to this, your care provider, if they work for an institution, will be required by their workplace to offer it. But you're in the position of power to actually accept or decline that offer depending on what you think you need. Knowing that actually, if you decline it, it's not like there's some really solid evidence saying that you've put yourself in a more or less dangerous scenario. So this really does fall into the hands of individual women as to whether or not they want to accept it or not because unfortunately it's so culturally embedded in obstetric and midwifery care that most clinicians aren't in a position to actually not offer it to you just because they get in trouble
Kirsten:
[35:13] It's worth asking the question if I said no what would you do what other things could you do to help provide you and me with some reassurance or heightened concern about what you're seeing at the moment and see what they say and that might get a recommendation for an ultrasound scan instead it might get a recommendation for more frequent checkups with a midwife you might be get a clue that you're going to actually be denied some other aspect of care or treated disrespectfully if you choose to say no and you've got to decide which battles you're prepared to fight on any one given day and maybe it's not worth holding your ground and saying no if it's going to make life more difficult further down the track.
Mel:
[36:00] And I guess the other final thing that I noticed women get offered antenatal CTGs for is if they go beyond 42 weeks or even beyond 41 weeks in some institutions. So a lot of institutions won't allow, inverted commas, allow women to go beyond 10 days after their 40-week due date. In my work, that's a lot more flexible.
Mel:
[36:25] I don't intervene in pregnancies that go beyond 42 weeks unless there's a really clear reason to. And so part of the antenatal assessment that hospitals will recommend when we present there to consult with them is daily CTGs for women who are pregnant beyond 42 weeks. I'm going to make an assumption that that's never been checked as a way of understanding well-being.
Kirsten:
[36:53] One of those four trials included amongst the women that they recruited, a category that they called risk of post-maturity. Now, your guess is as good as mine what that actually means. So it might mean women who are actually more than 42 weeks pregnant. But back in the 1980s, post-maturity was quite a different concept. And it was the idea that there are some babies whose placentas get funky and run out of juice before their time. And so their placenta is more mature than it should be at that gestational age. And so the post-mature fetus was small and had reduced lycor volume. But wasn't necessarily 42 or 41 weeks. They might be describing an entirely different thing to our current concept of what it is that we're talking about in this time. So that was one trial, and as I say, any of the individual trials were less than 500 people tops, and it didn't show an improvement in outcomes.
Mel:
[38:06] There you go because I mean I've had clients travel an hour for a CTG because that's the recommendation that the hospital has given them but I guess what I'm hearing is that we're no better equipped to understand the well-being of a baby whether we use CTG or intermittent auscultation or where we go using some other assessment I feel like I understand the gist of where you're going with this especially because we know that the only research that's available was done around 40 years ago and there's not been any done since and so there's no more extra information other than what they've managed to glean from that 1600 women and so all of the questions that I'm going to ask you is basically going to be the same answer is we don't know because there's no research but they're still using it in all the hospitals because they think it works but we don't actually know what a normal ctg is let alone an abnormal one we're all just speculating Okay, Kirsten's nodding. Yeah, that's our answer. That's our answer for today about antenatal CTG. So CTG in pregnancy.
Kirsten:
[39:20] Yeah, if you want a list of reasons that can be justified by the research as to when a CTG should be done in the antenatal period, the answer is never. And that's not that there might not be a reason. It's just that we simply don't know because no one's bothered to go and find the answer to that question. So, yeah, we just don't know. There might be particular conditions where women do much better if they have CTG monitoring, but at this point in time, we can't actually say what they are on the basis of the research that's been done.
Mel:
[39:54] Yes. Okay. And I guess the only other thing that would warrant a CTG in pregnancy is if the woman feels like she needs it. That's always a good reason for anything in pregnancy. But from the research, if you're a woman listening and you're thinking, I really don't want or I don't think I need this but I feel obligated to because my care provider seems to think that it's going to be important and integral in my care. I guess this could confirm your initial feelings about it. On the flip side if you feel like you want a CTG every single time that's completely fine just know that there's no evidence to suggest that that's going to improve outcomes for you. In fact the very small low quality evidence that is available seems to slightly lean towards the possibility that you could have worse outcomes.
Kirsten:
[40:42] Yes. And certainly if you have had a CTG done because people were concerned and you continue to still have a gut feeling that something's not quite right, don't think, oh, but the machine said things were fine, so I'll just not do anything. Do go and seek extra help.
Mel:
[40:58] Yes, that's right. I would prioritise your own maternal intuition over the information that you've been offered by flawed screening tool. All right. I think that answers our question. I mean, we've got nothing more to offer you because there's no more research. All right. That was CTGs in pregnancy. And Kirsten's going to stay with us for two more episodes about CTG in birth. And then also, is there ever a good reason to have a CTG? Those are coming. We will see you in those next episodes. 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, at Melanie the Midwife on socials and the show at The Great Birth Rebellion. All the details are in the show notes.
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