ļ»æEpisode 205 - Anti-D for Rh Negative Women
[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 and welcome to today's episode of the Great Birth Rebellion podcast. I'm your host, Dr. Melanie Jackson, and today we're talking about the use of ATD in pregnancy for women who have a negative blood group. So I've been a midwife for over 18 years and I've been caring for women through their pregnancy, birth and postpartum. So this is something that I do semi-frequently with my clients as there are a number of them who have negative blood groups.
[0:54] So today, this episode is just all about what I talk to my clients about with regards to their NTD choices and I just feel like you're all going to benefit as well. This episode is particularly for clinicians but also for women who are making the choices about this. But I'm going to talk a little bit about this. Student midwives and clinicians who are working with women who have negative blood groups, this episode is going to be super interesting to you because I give very specific detail for clinicians about which kinds of tests that you can send women for. So if you're new to clinical practice or if you're a student or you're trying to get your head around doing this yourself, then this episode is going to be really helpful just as much as it is for you women who are making choices about whether or not to have ATD in your pregnancy. This episode is sponsored by my dear friend and birth prep extraordinaire, Poppy Child from Pop That Mama. She's a doula and hypnobirthing practitioner and her online hypnobirthing course called The Birth Box has already helped thousands of women get ready for labor. Listen to this recent review of The Birth Box. The woman says, I'm a first time mom and I gave birth to my beautiful baby boy yesterday. day. I've been listening to the birth box on repeat for the past few months, including the day in which I went into labor. And I had the most empowering birth experience. And I can honestly say that listening to the birth box was a huge part of this success.
[2:22] Reframing the pain that you experience during labor can be a purposeful pain instead of a harmful pain. And that really helped me to know that and just being able to surrender to the wild ride that birth is and let my body take over was the most incredible thing and this is coming from a pelvic floor physiotherapist based here in Australia she says I will recommend it to all my patients and you know me I'm so picky about what I will endorse but I do get behind the work that Poppy is doing and in the birth box you'll learn tools to help you manage pain and how to stay steady when labour gets intense. It's all about giving you knowledge, confidence and a mindset that actually works when the big day comes and for the big days that will follow.
[3:12] Birth Box is rated five stars across the board. And with my code, Melanie, you'll get 25% off. So if you're preparing for birth, go to the checkout. You'll be so glad you did. The link is in the show notes. Use the code Melanie to get your 25% off.
[3:30] Now, as I said, this episode is specifically for women who have a negative blood group and for their clinicians who are caring for them. And, you know, all people have a blood type, either A, B, AB, or O. And then we have a rhesus factor, which is either positive or negative. So if you have a negative rhesus factor, your blood type would be A, B, AB, or O negative. So if you have a negative blood group, this episode is for you because you have some options to consider. some women don't even realize that if they're a negative blood group that this is going to affect their pregnancy. You might not even realize you're a negative blood group until you are pregnant when you have your first blood test. So this episode is for you if you're a midwife, healthcare provider, if you're responsible for sharing information with women about NTD, student midwives and doulas who are also passing information on to women so they can make informed decisions. What I also want to say here for you clinicians, if you feel like you need more support in your clinical practice, I've got something for you.
[4:40] I run the Assembly of Rebellious Midwives. It is primarily for midwives and obstetricians who want to provide evidence-based, woman-centered care. And together as a community, as an online assembly, we work through all the things we can do to be respectful, well-informed, and caring maternity care providers. So if you want to join the Assembly of Rebellious Midwives, just scroll down to the show notes below. All the details are there. These are the kinds of things we get into. Things that will optimize your critical practice feel free to click the link have a look at and explore and see if you'd be interested in joining the assembly of rebellious midwives.
[5:21] And as always all of the resources that I use to make every single podcast episode are in the podcast resource folder and if you're on the mailing list for this podcast you'll have access to that resource folder and you have been using it for every other episode but if you're new to the podcast, feel free to join the podcast mailing list. It means you get access to the resource folder where I add all the resources that I use for every single episode. There is a huge back catalog and you get access to that. You get immediate access once you sign up for the mailing list. And one of the resources that I used to create this episode was a book called
[5:58] Auntie D Explained by a midwife named Dr. Sarah Wickham. And that was the, this book was her second book, more up-to-date book about anti-D so if you're going to read one I would recommend anti-D explained which was written in 2021 which is 20 years after her first one on anti-D so don't get confused with those two options right so today I'll be talking about the reasons why you'll be offered a product called anti-D during pregnancy if you have a negative blood group.
[6:28] Or sometimes you will have heard it called ROGAM, which is like a brand name or product name for the Rhesus D immunoglobulin injection that we're going to call anti-D. So just for clarity and consistency in this episode, I'll use the terminology anti-D, but I'm still referring to this is all the same medication.
[6:47] Okay, so here we go. The questions I really do want to answer today will include, why do women with a negative blood group get offered anti-D during pregnancy and after birth? What is ATD and how and when is it administered? Do you really need to have ATD? What happens if you do or don't decide to accept it? What information could you gather to help you make decisions through your pregnancy and after the birth, which this would include the tests and screening options that are available to you so that you've got some information about if you, to help you decide basically if you want to accept ATD or not. All right, so we'll get started with some basics. And I already told you that some women have a positive blood group and some have a negative. So part of your very first antenatal or pregnancy blood tests will include the testing of your blood group and your rhesus factor. And they will also test for antibodies in these initial tests. So if you don't already know your blood group or you want to know if you have antibodies, This information is available on your very first pregnancy blood test if your care provider has been thorough.
[8:00] Okay, so if you get those results back and your blood group is positive, there's nothing more for you to do. But if you get those results back and your blood group is negative, the next very helpful thing to do is find out what the blood type of the baby's father is. Many of you will already know who the father of your baby is and some perhaps through circumstances of your own choices or as a result of an unsafe or dangerous situation, you may not know who the father of your baby is. And that's okay for these purposes. I hope you are safe. But if you do know who the father of your baby is, you can find out what their blood type is. That's one option. If you both have a negative blood group, again, nothing else needs to happen because your baby is going to have a negative blood group. And that can help you make decisions about what you might need to do next with regards to anti-D. So your partner can choose to go and find out their blood group. An easy way to do that actually is if they go and donate blood because they will check what their blood group is before doing all of that or you can get a blood test. So this would have to be of their own initiative. Your care provider isn't going to be able to write your partner a referral form to go and get a blood test. That would have to be something that they go and do off their own back.
[9:24] So now if you're a negative blood group and the father of the baby is a positive blood group, there is a possibility that your baby could also be a positive blood group. So now you need to make some decisions.
[9:38] But why is this so? Why do you need to make decisions? So the thing with blood groups is that you can't give a person, for example, if you were donating blood to somebody, you can't give a person with negative blood to.
[9:55] A rhesus positive blood. Even if the blood type is the same, so if you have an O negative person, they can't receive blood from an O positive person in part because they will develop antibodies against the positive blood. Their immune system will want to reject it. It's the same way if you contract a virus, your body or your immune system will make antibodies against the virus to try and fight it. It's considered a foreign body. And the same thing happens if a person with negative blood receives blood from somebody with positive blood. Their immune system will develop antibodies against it. It's a normal immune response. So in the case of blood types, a person with negative blood would develop an antibody called anti-D. So this would be a naturally occurring anti-D, and it's a naturally occurring antibody against positive blood group. So this is one way to develop antibodies. This is kind of like the natural way that your body would develop antibodies. However, this is part of the problem. This becomes a problem for future pregnancies if you've got antibodies against positive blood groups. The other way to get antibodies against a positive blood group is.
[11:16] If you accept a product called anti-D, which is what we're talking about today, the anti-D immunoglobulin, which can be given to you to prevent your body from making its own anti-D antibodies. These borrowed antibodies, they mop up any positive blood group cells that might enter your bloodstream before your body notices. And that means it prevents your body from making its own antibodies. It's kind of like the cleanup crew before your body realizes that there's positive cells in there that they need to respond to. So one question that my clients ask is, does every woman with a negative blood group who gets exposed to the positive blood of their unborn baby, do all of those women develop antibodies? The answer is no. Not every woman who's exposed to the positive blood of their baby will develop antibodies against positive blood groups.
[12:15] Now, because this is an under-researched area, it's difficult to know what the percentage range is of women who will develop antibodies if they're exposed to their baby's blood. And the old, old research that we have, which is over 50 years old now, suggests that if you're a woman with a negative blood group and you're pregnant with a baby with a positive blood group and the baby's positive blood enters your bloodstream and you don't have ATD, 10 to 15% of the time your body will develop antibodies. It's not a definite sure thing. Even if the baby's blood enters your bloodstream, the approximate chance that you will develop antibodies against a positive blood group is around 10 to 15%.
[13:07] So an important fact to know here is that not everybody's immune system will be stimulated to make antibodies, but there isn't any test that we can use. There's no way to determine whose body will create antibodies and whose won't. So the job of the anti-D immunoglobulin, the one that would be injected and given to you, is to prevent your body from ever starting to make these antibodies in the first place. But in the hypothetical situation that you're carrying a baby with a positive blood group and there is a sensitizing event where the baby's blood ends up mixing with your blood, there's a 10 to 15% chance that you'll develop antibodies if you choose not to have the ETD injections.
[13:53] Now, this is a good time to talk about the discovery of NTD and also how it's made before we keep going. Because this NTD story that I'm about to tell you, and I'm going to read it verbatim from an article that was written by the International Confederation of Midwives, and I've linked this article in the resource folder if you want to have a look at it. But I feel like this little story is a nice way to understand a bigger part of the NTD story. and I'm just going to read it verbatim. So the discovery of the rhesus factor was born of a research race during the late 1930s and early 1940s with several studies published almost simultaneously. They identified the rhesus factor and soon after linking, soon after they linked it to the hemolytic disease of the baby, of a fetus and a newborn.
[14:46] Following this discovery, living babies could be treated with a blood transfusion immediately after birth. However, by then, the effects of the disease had often already caused major complications in the child. It wasn't until the mid-1960s that a preventative treatment was discovered. So this is NTD, and multiple people are attributed to the discovery of NTD treatment, one of which was John Gorman, an Australian doctor working in New York in the USA. Gorman and his team ran what would these days be considered entirely unethical experiments on inmates of a correctional facility in New York, and the ATD antibody was harvested from the blood plasma of rhesus-negative prisoners who had been sensitized with positive blood, and I'll talk to you about that in a minute. Okay.
[15:44] These antibodies were then injected into unsensitized prisoners, so into prisoners who, so prisoners with negative blood group were then given the anti-D that was harvested from other prisoners, and they tested what would happen, and this afforded them complete protection from sensitization when exposed to positive blood. So this is known as a paradoxical treatment, introducing the very thing that you're trying to avoid, antibodies. They introduce those and that prevents the person's body from creating antibodies. So keen to test this knowledge from these very unethical studies is.
[16:34] So Gorman wanted to test it on a pregnant population. However, that was one step too far when they considered ethical limitations of research. And so Gorman recruited his own sister-in-law, Kath Gorman, and Kath had a negative blood group and her husband, Jonathan's brother, was positive. So Kath consented and was injected with the anti-D. And the story goes is she went on to have seven healthy children using this anti-D.
[17:04] So what we can know from this little excerpt is firstly that anti-D, the product itself, is in fact a blood product. Some people think it's like an immunization or a medication. It's not. It's a blood product. So if you didn't know that before, you know now. And this often factors into women's decision making around whether or not to take anti-D. It's an immunoglobulin harvested from blood plasma. So it's not a medicine or an immunization, as I said, it's a blood product. And this is the way it's made. So it kind of, the story that I just told you alluded to how it was made. But now, modern times, a person with a negative blood group submits themselves voluntarily, unlike these poor prisoners who were subject to experiments, they submit themselves for voluntary sensitization for the sole purpose of becoming anti-D blood donors. So there's people out there all over the world with negative blood groups who voluntarily accepted small doses of positive blood in a controlled setting in the hope of developing antibodies. So then once they get exposed to the positive blood.
[18:23] They then have their blood tested to see if they did develop antibodies. And then if they did, they're accepted onto the donation program to be a donor for the sole purpose of providing and creating anti-D. So this voluntary sensitization is achieved. Again, they have to receive multiple and repeated transfusion of closely matched positive blood. But not everybody creates antibodies. even when they're intentionally trying. And in fact, in this article that I'm reading from, the woman who wrote the article, the one for the International Confederation of Midwives.
[19:01] She explained that she required three exposures of 40 mils of positive blood in order to develop the antibodies. The first two exposures had no effect. 40 mils is a lot. That's not as much as what you would get exposed to if your baby's blood mixed with yours. She had to have three exposures before developing antibodies and then when they test and went yep you do she can now donate blood for the purpose of creating ATD the interesting thing is though is that yes it's a blood product but when you have one single vial of ATD it's not from one single person the it's plasma which is part of the blood product that contains the ATD and the product is pooled. So it's a number of donors, blood, who's in the one vial.
[19:55] So now we know how NTD is made, how it was discovered. It's a pooled blood product in the form of an immunoglobulin in blood plasma. And it's used for women with negative blood groups who are pregnant with a baby who might be or is a positive blood group.
[20:14] And before we go on, let's answer one more question. He's.
[20:19] Does the blood of a baby normally enter your bloodstream, the bloodstream of a pregnant woman?
[20:29] And the answer to this question is no. Normally in pregnancy, your blood would not mix with your baby's blood or vice versa. Your blood vessels are incredibly closely interwoven, but they're not mixing blood. The nutrients and oxygen and all the good stuff that you need to give your baby is exchanged from your bloodstream into the baby's bloodstream through a kind of seeping out from your blood vessels and soaking into your baby's blood vessels. So the actual blood cells and blood elements that are floating around in your bloodstream never leave your bloodstream. The nutrients and all the good stuff and sometimes the medication and the bad stuff and smaller viruses can seep out of the blood vessel, your blood vessels and soak in to your baby. So theoretically, none of your red blood cells or the baby's blood cells should ever mix or switch over bloodstreams. So it's a pathological situation if your baby's blood is mixing with yours. So just by being pregnant with a positive, a baby with a positive blood group, if you've got a negative blood group, doesn't put you at risk of your blood mixing. It's not a normal part of pregnancy. So then the question is, how would this occur? What happens? Why would your baby's blood mix with yours?
[21:57] So blood mixing can occur with what we call, in maternity care, we call them sensitizing events. And this can include bleeding events or invasive testing events, including like an amniocentesis or an ECV, external covalic aversion, if you're trying to turn a breech baby. And the bleeding events might include things like miscarriage, trauma or force onto your belly like a car accident, or if you've been a victim of violence or you've had a heavy fall or again I just mentioned during the like during some medical procedures that might cause an interruption between the babies and your blood vessels. Now again this isn't to say that every sensitizing event actually results in you having contact with your baby's blood but these are times where there's an increased chance a risk of it happening.
[22:50] So for this reason, if you experience a sensitizing event through your pregnancy, your care provider may want to do blood tests to check if there's been any blood mixing. And there are blood tests, and I'll talk to you about them. There are blood tests that can count how many of your baby's blood cells have entered into your bloodstream and measure them. And it can also test if you've started making antibodies against your baby's blood group. And then they'll use these blood tests to make decisions about administering ATD or how much. Sometimes if you've had a sensitizing event, your clinician will just give you ATD and do the tests, but give you ATD anyway, regardless of the result of the tests. But if you have a negative blood group and you do have a sensitizing event, please do know that there are blood tests that can check if there even has been any mixing during these sensitizing events.
[23:50] And so this is a point, a decision-making point that you can make. And this is something that I offer to my clients. If there's been a sensitizing event, and actually, in fact, I forgot to mention birth is considered a sensitizing event. But if you've had a sensitizing event, there are blood tests you can do to check if there's been any mixing. There are blood tests you can do to see if any antibodies have developed. And then you can use that information to decide if you also do want to accept ATD. You don't have to accept ATD straight up just because there's been a sensitizing event. As I mentioned earlier, the chances of you actually.
[24:28] Developing antibodies from an exposure is around 10 to 15 percent and that is not a confident statistic either because it's from very old studies. We don't have a lot of new research about the use of NTD and the possibility of sensitization.
[24:46] And the point I want to bring up here is that if you've got a negative blood group, often NTD will be offered to you as it's assumed that you will want to take it but it's always used medically in pregnancy well always usually as a preventative or prophylactic strategy not always as a treatment option in the event of an actual exposure a lot of what you'll be offered is prophylactic ATD as a just-in-case measure and so there is still a lot of choice within this you don't have to accept every dose if you don't want every dose.
[25:23] So let's talk about that, the routine administration of ENTD. So what is just routinely offered in most countries, most parts of the world?
[25:35] If you have no emergencies during your pregnancy, none of these big dramatic sensitizing events, you'll be offered a minimum of three doses of NTD. One around 28 weeks, then again around 33 or 34 weeks, and then again within 72 hours after birth. And fun story is when I was a student midwife about 20 years ago, there was a shortage of NTD. And when there's a shortage of NTD, they just stop giving the antenatal doses. They just give the post-birth doses because birth is considered at a sensitizing event. However, when there's an abundance of ADD, they will recommence the antenatal doses, which gives you some idea of kind of how...
[26:24] Important some of the maternity care system believes anti-D to B is that when there's a shortage, they kind of go, righto, we'll have to stop giving the antenatal doses.
[26:35] But before each dose, your care provider, well, at least this is what I do, your care provider will want to check your antibodies through a blood test to determine if there has been a mysterious, unchecked, surprise sensitizing event and you've started to develop antibodies and before each dose before the 28 week and 34 week dose they want to check your antibodies again to see if they need to give you more ATD however some clinicians will just administer the ATD before even checking if you've got any antibodies now historically the problem with just giving every woman with a negative blood group anti-D at 28 and 34 weeks and after birth is that some women will receive anti-D when they don't even need it because their baby's actually got a negative blood group and historically there has been no way to determine which woman would benefit from anti-D because their baby has a positive blood group and which has a negative blood group because if a baby has a negative blood group you don't even need atd but now here in australia and lots of parts of the world we can actually check taking a blood test from you the mother.
[27:56] There are free-floating sort of fragments of your baby's genetics in your bloodstream. We can find those fragments and test them and find out the blood group of your baby. And you can do this from about 15 weeks. And this has reduced the amount of ENFUD that we need to use because we can detect which women, which women with a negative blood group are also carrying babies with a negative blood group. And then they don't need NTD in a similar way if the woman and the partner are both negative blood groups they don't need NTD so now we can do testing in early pregnancy to find out if the baby what the blood baby's blood group is and then further whittle down which women might benefit from NTD so if you're keen to know early in pregnancy if you even need to consider the NTD conversation you just need to ask for fetal rhesus testing or fetal blood type testing and then your care provider can provide you with a referral for this and before we go further I want to give you some information about what could happen if fetal blood your baby's blood enters your bloodstream and no anti-d is given so let's talk about the possible outcomes of that just for the purpose of information.
[29:18] So if in this current pregnancy, you're exposed to your baby's blood through a sensitizing event and it's positive, either nothing will happen, that's about 85 to 93% of the time, nothing will happen. You will not develop antibodies. Again, take that statistic with a grain of salt because the research is very old about that. Or you've got a 7 to 15% chance of developing antibodies.
[29:46] Now the thing is is that those antibodies don't affect your current baby and they don't affect you so this could potentially become an issue for future babies if your future babies are a positive blood group so if you are hearing this all for the first time maybe your care provider's not on the ball and you think oh my goodness I'm a negative blood group what if there's been some kind of mixing there is actually no risk to your current baby if you start developing antibodies but let's say you are exposed and you do develop antibodies when you become pregnant with your next baby you now have circulating antibodies whose entire job is to fight positive antigens positive blood groups so then when you become pregnant with your next baby if your baby has a positive blood group These antibodies can cross through the placenta into your baby's bloodstream and literally start attacking your baby's bloodstream. This is why the outcomes for these babies are poor. There's things like ABO incompatibility, anemias, they can have.
[30:57] It's obviously a higher risk of miscarriage. And if these babies do make it through to full-time, then there are things that can be done now in a modern time that we know what the problem is with blood transfusions. However, it's not good outcomes for the baby, and that's why the medicine of anti-D came about. And as I told you about earlier in the story, one of those anti-D donors, one of the women, needed three exposures to develop any antibodies so it's not a guarantee and this is why we're grateful that scientists realize so if you go with me on how this anti-d works is let's hypothetically say you've got a positive a baby with positive blood group and its blood mixes with your blood and you have a negative blood group and then fortunately you've accepted an injection of anti-D. What happens is, is the anti-D is the cleanup crew. It's like immediate immunoglobulins, which start to clean up and get rid of these positive blood cells that had been discovered before your immune system even realizes that where they were there. And then it doesn't start to create its own antibodies because the anti-D has done its job. It's the cleanup crew and then, and has cleared out all those positive cells. And so your body is none the wiser, doesn't even need to make antibodies. That's the purpose of ETD.
[32:21] And I love the way that Sarah Wickham explains this. This is how she explains this situation with regards to taking the anti-D. She says, it's the only drug that I know of that first of all is given to a person who doesn't physically benefit from it because the woman herself doesn't physically benefit from it, particularly when it's given in pregnancy. It's given to the possible detriment of another person the unborn baby because we're yet to really understand if it has an impact on the current baby who also doesn't physically benefit from the anti-d and anti-d is given for the benefit of a person who doesn't yet exist and who might never exist and she's referring to the future baby that may or may not exist so whenever you're making decisions about ATD, you're always making those decisions for the purpose of your next pregnancy and next baby. So this brings up conversations around, are you having a next baby? Is this your last baby? Do you ever plan on having another one?
[33:28] So Sarah makes the point here is, you know, let's say you have no more plans for any more babies. Maybe your partner's had a vasectomy. This is your last baby because you've had all the babies you want to have. Maybe you're getting older maybe your family is full and you're done in that circumstance you can ask yourself why would I accept ATD should I accept ATD it doesn't actually benefit from this pregnancy the benefit comes in the future pregnancies so that is the what why how and whatever about ATD so we know why you might choose to accept ATD and that's to prevent the development of antibodies bodies against the blood of your future babies,
[34:11] if they are a positive blood group. But what about the downsides of ETD? You know, what are the reasons why maybe you wouldn't accept it?
[34:19] Now, firstly, we already discovered that it is a blood product, and some people have an objection to accepting a blood product. In part, there can be a cultural or religious objection, but there also is a risk, albeit very small these days, because we're working at properly screening blood donors. But there is a risk of accidental viral transmission from the ATD blood product to women who are receiving the blood product, particularly because it is a pool. There's multiple donors in one single little vial. So there's that, the risk of possible viral transmission. As hard as we try in these services to ensure that the blood is not contaminated, that is a possibility. It's always a possibility. The next risk of the NTD injection is the risk of an anaphylactic reaction for you, the mother to the ATD injection. And that's why usually ATD is injected in a facility or a place or your midwife should have something to counteract or reverse an allergic reaction with them, something like adrenaline. And it's hard to say how common a severe allergic reaction is, but the literature suggests that approximately one in 100,000 injections would result in some kind of allergic reaction.
[35:46] Now, the other risk is to do with user error. So, NTD is supposed to be injected into a large muscle. We usually put it in your bone muscle. It's an intramuscular injection. And if per chance, it should accidentally be injected directly into your bloodstream. So, when we do an injection, particularly an intramuscular one, we insert the needle and then we draw back a little bit to make sure that we're not in a blood vessel. If blood comes out, we need to reposition that needle. But if per chance it's directly injected into a bloodstream instead of the muscle, this can cause sudden circulatory system symptoms. So it's important to note that that is a user error issue. And the other risk is obviously with a contamination issue with the actual product. And then the only inherent risk within your body is the anaphylactic reaction. But it is important to note that there is very little research on the impact of anti-D administration. We know it works. We know it prevents this isoimmunisation, prevents you from making...
[36:57] Antibodies, not all the time, but it can reduce it right very small. You know, one or two percent of the time, ATD isn't effective, but the rest of the time it is. But it's important to note particularly that the leaflet, the information leaflet for ATD specifically states that the safety of this medicinal product for the use in human pregnancy has not been established in controlled clinical trials. They haven't tested ATD on pregnant women. They just use it on pregnant women, but it's not actually ever been tested.
[37:30] So we've never actually checked if there are specific short or long-term impacts to the woman or her current baby. And this is not a criticism, it's just the facts. And this is something that's been declared in the medication leaflet itself. Never been tested on pregnant women. So we just don't know if there are other risks other than the immediate big ones like anaphylaxis or a reaction to the accidental IV administration.
[37:58] Okay, so I'm going to run you through a little scenario that plays out in my own practice when I care for women who have a negative blood group. So first, of course, I offer them that antenatal blood testing initially at our first appointment where I'm interested in finding out their blood group and if they already have antibodies. Again, if the blood group is positive, there's no conversation about anti-D. But if it's negative, this is where we start explaining the options. We also are importantly checking who the baby's father is and determining their own blood group if they want to and checking if the antibodies are positive or negative. If they're negative, the woman has not already developed anti-D antibodies. If it's positive, she's already had a previous exposure and she's got antibodies.
[38:48] If it's negative, that tells me already that this current baby is safe from its mother's antibodies in pregnancy. So next, I start to give some education about possible sensitizing events. So the ones I explained before, and I talked to the women about reporting these things, if this, this or this happens, any bleeding events, any sudden impact to your abdomen. I would know if she had any invasive medical testing. All these things miscarriage uh sensitizing events then i if the woman is a negative blood group and the partner the father of the baby is a positive blood group then i offer them a referral to go and get the maternal blood test that can detect.
[39:36] The blood type of the baby so we can find out the baby's blood group and then if the baby's blood group is negative we don't have to do anything else again the ATD conversation doesn't need to happen because you've got a woman with a negative blood group and a baby with a negative blood group and if you're a clinician listening to this and you're wondering what is that test in the resource folder I've put the name of the test how it all works and a few of the facilities that provide that particularly if you're here in Australia you'll find that information and you can just do a search in your area of where you might get access to that test and again if you're a clinician and you're thinking oh my gosh some of this stuff would be so confusing what do I do if I have a client who's got a negative blood test if you're feeling not confident I would really encourage you to join the assembly of rebellious midwives because in there we make sure our clinical practice is up to scratch and you know what to do in all of these scenarios You don't have to ask questions. You will just keep learning together.
[40:36] So now, already in my own clinical practice, I know the woman's blood group. If she has antibodies, if the woman chooses any other tests, we could also know the baby's blood group too. If they know the father's blood group, then we can make decisions about if we need to go further or not. So only if the woman is a negative blood group and the baby is positive do we
[40:59] need to be talking about ongoing testing for ATD. And a little factoid here, with regards to the ATD medication.
[41:09] The antibodies that you get, so if you get an ATD injection.
[41:16] I have had people say, well, how long does the ETD last? Am I like immunized forever? Although it's on immunization. Am I immunized forever? The fact is, no, you're not. The antibodies that are administered through the ETD injection last around three months. They do their job and then they break down and leave. There's no remaining remnant of those after about 12 weeks. So it's not like you can have one single shot and feel like it's not a set and forget kind of thing. However, if you are exposed to your baby's blood and you do develop antibodies, you have antibodies for life. Your body's just going to keep making those. So here we start to see why women might choose the NTD, particularly after sensitizing events, because you can't really stop your body from making the antibodies. Once it's started, it doesn't stop. However, if you get the injection, it doesn't last and circulate in your body. It does have to be re-administered. At those intervals that we spoke about during sensitizing events and in each pregnancy.
[42:20] Okay, so that's the early kind of checking and testing that we can do for women in the first trimester. Then the opportunity for your first ATD injection is at 28 weeks of pregnancy if you haven't already had any sensitizing events prior to that. The routine administration happens at 28 and about 34 weeks. Now for me in my practice, I would first at this 28-week juncture, it's a nice opportunity to also check a woman's iron status if she's happy. So I'll offer her a full blood count, including iron studies and an antibodies test. And this, if again, if it comes back negative, there's been no exposure of the fetal blood to the maternal blood. Now this is a decision-breaking point for the woman. I ask her, I say, look, you've got an opportunity here to have some NTD if you would like. However, you've got no antibodies. It appears as though there's been no sensitizing event and no mixing of fetal blood. Would you still like NTD? And to date, 18 years later, I haven't had any clients.
[43:30] Take the opportunity to have prophylactic ETD. So that's been my clinical experience that if you actually offer women this information that I've just explained to you and they've got all of the test results and they understand then they're really capable of making decisions about whether or not they want to accept ETD. So this is the first opportunity and then the next is at 34 weeks. Again, we have the same conversations.
[43:58] And then the next sensitizing event is the birth.
[44:01] And again, it's a decision-making point for women. Do you want to have ATD at birth? So then after the birth, I take blood from the baby, but I don't take it from the baby. I take the baby's blood from the placenta. And this can happen hours after birth. So for me, my clients, you know, it's optimal cord clamping means you don't do it until the cord is empty of blood. And then often we wait for the placenta to be born. And then when the dust settles and everybody's chilled out a little bit, I'll actually take the baby's blood from a big juicy vessel in the placenta because all of the blood in the placenta is the baby's. I don't need to take it from the cord soon after birth. I don't have to cut the cord just to get a blood group for the baby, you can extract blood from a vessel in the placenta. So I do that and then that is sent off in a blood tube and I check the baby's blood group. Even if the woman's already had that antenatal test that told them what the baby's blood group is, I'm taking the blood anyway. I always like to confirm the baby's blood group with an actual blood test. And then the other test that goes on that form is a DAT, D-A-T. So if you're the one writing the pathology form, a DAT stands for direct antigen test, I believe, or you can just write Coombs. So...
[45:31] Blood group in Coombs or blood group in DAT for the baby. And then you also test the mother's blood and she has a Kleyhauer test. It's spelled K-L-E-I-H-A-U-E-R. I always don't know how to spell it. I have to look it up every single time, but that's what you would put on the pathology form for the mom. She has a Kleyhauer and the Kleyhauer counts for the amount of fetal blood that's in the maternal bloodstream. So then the results of those should come back within 24 hours, which is enough time for the woman to make her final decision does she want anti-D after the birth or not. An anti-D after the birth needs to be given within 72 hours because if there has been mixing of the fetal blood in the maternal blood the woman after 72 hours would start making antibodies. So you give the anti-D before the woman's body has an opportunity to start making antibodies.
[46:27] However, if the DAT or the Coombs from the baby is negative and the Clihauer is negative, this indicates that there has been no fetal or maternal blood mixing. And then the woman can use that information to decide if she wants to take the opportunity for this last anti-D dosage. Again, only if the baby's blood group is positive, of course. So alternatively, if there's lots of fetal blood mixing in the woman's bloodstream, she may actually need more doses of ETD.
[47:05] And so that post-birth blood testing is probably the more important blood testing because it's a sensitizing event. These aren't really the prophylactic doses like in the 28 and 34 week doses, which are kind of just routine prophylactic doses. The birth is considered a sensitizing event, but you can help gather information about whether or not you need it as a woman or as a clinician. If you want to give the woman more information about her options, using the DAT result from the baby or the Coombs result from the baby's blood test and the Kleihauer result from the mum's test, they're both negative and you present those to the woman to say, look, there, appears not to have been any mixing. Would you like the last anti-D dose? They can make a decision about yes or no to have that final dose.
[47:57] That is what I have for you today regarding anti-D. And of course, if you're a clinician and you have way more questions about how to care for a woman who's got a negative blood group and whose baby has positive diabetes.
[48:11] Blood group, then please do join us in the Assembly of Rebellious Midwives. There's a whole group assembly of midwives and clinicians there ready to help you optimize your clinical care for women. And if you're a woman listening to this with a negative blood group, I hope this has helped clear up some of the decisions that you might need to make around the use of ETD in your pregnancy. I'm Dr. Melanie Jackson, and I will see you in the next episode of the Great Birth Rebellion podcast. 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.
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