EBB 329 – Q & A about Blood Types, Rh Incompatibility in Pregnancy, and the Rhogam Shot

Dr. Rebecca Dekker – 00:00:00:

Hi everyone, on today’s podcast we’re going to do a Q&A all about blood types and blood incompatibility in pregnancy. Welcome to the Evidence-Based Birth Podcast®. My name is Rebecca Dekker, and I’m a nurse with my PhD and the founder of Evidence Based Birth®. Join me each week as we work together to get evidence-based information into the hands of families and professionals around the world. As a reminder, this information is not medical advice. See ebbirth.com/disclaimer for more details. Hi everyone, and welcome to today’s episode of the Evidence Based Birth® Podcast. Today, I am joined by Sara Ailshire, a doctoral candidate and second year research fellow at EBB, who is going to join me in talking about and answering some questions on blood incompatibility in pregnancy, including Rh incompatibility, which is a fascinating topic. And Rh incompatibility is a question that we get asked about a lot. So we addressed it in detail at the Evidence Based Birth® Conference in the spring of 2024, as well as answering lots of questions about it in our Pro Member forums. As a reminder, if you ever want to personally ask me or other researchers at Evidence Based Birth® a question, you can do so inside the EBB Pro Membership. And in fact, this summer, we released a handout just for Pro Members all about Rh incompatibility and RhoGAM shot for Pro Members to print and share or email to their clients and colleagues. You can learn more about how to get access to all of our handouts in our PDF library just by visiting ebbirth.com/membership. We have monthly, quarterly, and annual membership options available, as well as scholarships. And if you’ve ever wanted to access the full range of resources at EBB, I highly recommend getting involved with our Pro Membership because not only, are you supporting our work and the work we do to publish research, but you also get that full library of PDF handouts, access to a Doula Mentorship program, a midwife brunch and learn program, all of our continuing education workshops and courses, and of course, direct access to ask our research team questions about the evidence. So today we’ve chosen some questions and answers about Rh incompatibility to share with you here on the podcast. And so, what we’re going to cover are three main topics. Number one, the science of blood types. Number two, we’re going to talk about Rh incompatibility, as well as ABO incompatibility in pregnancy. And then third, Sara and I are going to talk about some of the interesting things we’ve learned studying the evidence on this topic. So Sara, welcome back to the Evidence Based Birth® Podcast.

Sara Ailshire – 00:03:00:

Hi, Rebecca. I’m happy to be back.

Dr. Rebecca Dekker – 00:03:01:

Okay. So we have a lot to cover today. And I was wondering if you could start us off by just kind of giving us an overview of the science of blood types. Because what we found in talking with our Pro Members and our team members about this is a lot of people kind of don’t have that foundational understanding of blood types. So what do people need to know?

Sara Ailshire – 00:03:25:

Sure. So you would think that, you know, given how important knowing your blood type is, how important blood is, that there’d be a wider general knowledge about it. But a lot of people don’t even know the basics. It’s not their fault. It’s just maybe something they’ve not been exposed to. Most people though are familiar, at least with the different main blood types. So A, B, O, and also having a positive or negative blood type. But there’s a lot more to blood than that. So in order for us to be able to talk about and answer those questions about our blood incompatibility or A, B, O incompatibility in pregnancy, I thought it’d be important for us to go over the basics of the science of blood. So let’s just start at the very beginning. What are blood types? Blood types are based on the presence or absence of antigens or proteins on the surface of your red blood cells. You can think of these antigens as little tags on your red blood cells so that your body recognizes those cells as belonging to you. If you’ve ever been to a summer camp or your children have, you may have written your name in your shirt, written their names in their shirt, hoping that, you know, those shirts belong to them and they’ll come back with them, right? It’s kind of the same idea. 

So the two most common types of antigens on human red blood cells are the ABO antigens and something that we call the Rh-factor or the plus or minus positive or negative antigen. An Austrian scientist named Karl Landsteiner was actually the first person to discover the ABO human blood types. And he did this in 1900. So it really hasn’t been that long that we’ve even known about the existence of human blood types. He found that when he exposed the blood of one person to another, that sometimes the blood would clump up or agglutinate. It was through these experiments that he discovered these types of blood, A, B, and O. And then eventually the four blood types that we are most familiar with, A, B, AB, and O. Based on this research, an American doctor named Ruben Ottenberg was able to perform the first successful blood transfusion in 1907. And this is really important. Prior to this, blood transfusions didn’t always work. Oftentimes, it did not work because people would get the wrong type of blood. And I think, Rebecca, you’re going to talk a little bit later about transfusion science. Yeah, so it’s really important that you get the right type of blood for you. 

Otherwise, it can have really serious deleterious effects. And whatever you’re trying to treat with that blood transfusion, you actually make things worse. Landsteiner also later, you know, in that early part of the 20th century, discovered that we inherit our blood type from our parents, which is going to be important for us to remember when we talk about blood and compatibility in pregnancy. And his work was so important that in the year 1930, he won a Nobel Prize for making these important discoveries about blood. So how does ABO blood work? Well, somebody who has type AB blood has both the A and B antigens on their red blood cells, and they do not have the antibodies for the A and B antigens. That means that their body does not make an immune response, does not attack A and B antigens, because it recognizes that as being part of their body. Those names are on their T-shirts, so to speak. Somebody who has type O blood, however, will have neither the A or B antigens on their blood cells, and their body will attack or produce antibodies against A and B antigens. So somebody who has type A blood has the A antigen. Somebody who has type B blood has a B antigen. And people who are type A will recognize type B blood as foreign, and people who are type B will recognize type A blood as foreign.

Dr. Rebecca Dekker – 00:07:05:

It’s almost like they see them as invaders and want to attack.

Sara Ailshire – 00:07:10:

Exactly. Yeah, their body recognizes it as almost like a disease or almost like something dangerous that they have to fight against. Okay. The second common antigen on human blood cells comes from the Rh group. And that’s where that positive or negative that accompanies R, A, B, or O comes from. The positive or negative of your blood type refers to being Rh positive or Rh negative. So when we say that we have positive or negative blood, we’re simply indicating whether or not the Rh factor or Rh antigens is present or absent. So for example, my blood is type B positive, which means I have both the B and the Rh positive antigens. There’s eight common blood types I think most people are familiar with. And it’s A positive and negative, B positive and negative, O positive and negative, and then AB positive and negative. However, there’s over 600 known blood proteins or blood antigens. That means that there’s many, many other types of human blood types, but these are pretty uncommon.

Dr. Rebecca Dekker – 00:08:18:

Yeah. And I think it’s important for us to know, again, this basic principle, your body recognizes your own blood antigens and also recognizes when there’s something foreign. And sometimes this can be really important for knowing your own blood type, if you need a transfusion, for instance. And you had mentioned, speaking of rare blood types, that Henry VIII, they think he might’ve had a rare blood type, which is why he had trouble having children?

Sara Ailshire – 00:08:47:

Yeah, they think he had something called like the Kell blood type. They don’t know for sure, of course, because long dead had-

Dr. Rebecca Dekker – 00:08:53:

They haven’t tested his DNA. Yeah.

Sara Ailshire – 00:08:55:

Yeah. But and this is something that is also X-linked, which means that, you know, people who have two X chromosomes might be carriers and people who have one X chromosome. You know, that’s all they have. So they’re really affected by it. And this Kell blood type is it’s a type of rare blood group that can come from people who are Euro-descended. And in people who are X, Y, it can have some negative effects, sometimes on their fertility, sometimes on other aspects of their health. So that’s just one sort of interesting tidbit.

Dr. Rebecca Dekker – 00:09:26:

So, yeah, we all mainly know or hear about like a positive, a negative, et cetera. But there’s these other tags on people’s blood cells that are more rare.

Sara Ailshire – 00:09:36:

Absolutely. Yeah. And… It’s really fascinating when you get into it. Like I knew some of the basics of blood, but I didn’t realize just how many blood types were out there. And also all the work that goes into figuring out what those blood types are and making blood available for people who have those rare types.

Dr. Rebecca Dekker – 00:09:54:

And you mentioned like blood types are inherited from our parents. So what connection does that have with like our ancestry? And do you have any thoughts to share on that?

Sara Ailshire – 00:10:05:

Sure. So something that we came across in our research into Rh incompatibility is that the Rh blood type, particularly Rh negative, is not super common. I think something like 15% of people in the United States have this blood type. But I think worldwide, the incidence rate is something like 6%. It’s really variable. So it’s a lot more common, this Rh negative blood type, in places like Spain or Morocco than it is in Japan or China. And for example, I have type B blood. And something I’ve always found really interesting is that type B blood is way more common in parts of South Asia than it is in parts of Europe, for example. Historically, people tended to have children with other people who came from the same place as they did. They weren’t going super, super far. Now we can get on an airplane and go halfway across the world in a day. And just a couple hundred years ago, that voyage would take months, right? So most people hung out in the same place, met people in the same place, had kids there, and repeated the process. That means that we see some shared characteristics in people who have ancestry in one place compared to what we see in people whose ancestors came from somewhere else. And a good way to think about this, I think, is thinking about people who have blue eyes or have red hair. 

Now, there’s all sorts of people around the world who can have blue eyes or red hair, but we tend to see a lot of those people having ancestry in Northern Europe. Those are recessive traits that were pretty common there, and people from that place met, married and had kids with other people from that place for a long time, kind of keeping that trait going, kind of concentrating it in that one area. So again, it’s something that all people could have. It’s not that people there are significantly different. It’s just that if you have kids in the same place, you’re going to pass on some of those traits over and over again. And this comes up in blood because ancestry can be really important, especially for people who have rare blood types. So in the US, it’s really important that if you can, if it aligns with your beliefs and your health needs. For people to be able to donate blood, especially for people who have those rare blood types or who might come from communities who are underrepresented in blood banks. For example, people who have African or African American heritage are more likely to have a rare blood type called RO, which is kind of part of the Rhesus antigen group. And that blood can be used specifically to help people who have sickle cell disease. And something I found while doing some of the research is that there’s even this thing called the American Rare Donor Program in the U.S., that helps people who have rare blood, kind of figure out their blood type, can even help their relatives figure out if they have that same rare blood type, remembering that our blood is inherited from our parents. And it can help people who have rare blood type who might need blood for surgery, for transfusion, make sure that they can access the blood that they need. So I thought that was really interesting and a really cool resource.

Dr. Rebecca Dekker – 00:13:02:

And then one more thing about inheritance, I’d love for you to answer before we move on to the next subject, Sara, is, is it a simple inheritance? Like I know some things are more complicated, like, you know, maybe the color of your hair or some of those other things, height, for example, I think has hundreds of genes that determine your height, but with your blood type, is that like simple inheritance or is it more complicated?

Sara Ailshire – 00:13:27:

It’s pretty simple, actually. So all people have, you know, two copies. I’m going to say very simple terms here, like the gene for your blood type, you get one from each parent. So for example, I’m B positive, my mother is O, my father is B, I had maybe a 50/50 shot of being B or O, because my father’s parents, one of them, I think was B, and one of them was A. And you can kind of make these little charts to figure out what those are. So you can be homozygous for a trait, which means you have two copies of the same one. And the O blood type only appears if you have two copies of O. However, there’s lots of people like me out there who I have one copy of B and one copy of O. And for my father’s parents, they probably each had a B and an O and an A and an O, explaining how he could have the B blood type and not A or AB. So that’s just a really, I think, interesting example of how, you know, this type of simple inheritance works. And there’s, I think, a few other human traits where this occurs, like if you can roll your tongue or I think if your earlobes are attached. But it’s just a fun way to kind of think about all the different ways that we, you know, get things from our parents. Sometimes it’s more complicated, like you said, with height or hair color, eye color. And other times it can be pretty direct, like with blood type.

Dr. Rebecca Dekker – 00:14:53:

Okay. And so knowing your partner’s blood type might be helpful as we start getting into incompatibility. So for example, you know, if I was a negative, like an RH negative, and my partner was RH positive, then there’s a chance that our child could be like positive as well. So knowing the blood type of the other contributor to your child’s DNA is really important.

Sara Ailshire – 00:15:18:

Yeah, absolutely.

Dr. Rebecca Dekker – 00:15:20:

Okay. So let’s move on to, you know, that kind of leads into incompatibility because we talked about blood types. Now we’re starting to talk about inheritance. And so exposure to different blood antigens can cause the body to create an immune response. And this is something that we’re really sensitive to in the hospital when we’re providing blood transfusions to someone else, or perhaps on the battlefield. If somebody, you know, experienced a traumatic wound in war and is receiving a blood transfusion, it’s important to know their blood type. It’s important to know the blood type of the donor because foreign blood or blood that is not recognized as your own can create a response where the body attacks that blood. And as a nurse, when I used to administer blood to people in the hospital, we had to do so many different checks to verify, re-verify, and verify again the blood type of the person who is receiving the blood, the blood type of the donor. We had to have a chain, like a record of transfer of that blood so you know it had the correct label. And then we also had to monitor the patient for a good 30 minutes, you know, in person and then frequently after that because of, you know, the chance of somebody having a rare blood type that, you know, you were not aware of. But for the most part, you know, we think about blood incompatibility when you’re giving donations and transfusions, but it can happen in pregnancy because in the case of pregnancy, your blood as the pregnant person can become exposed to by the blood of the fetus. 

And so we get a lot of questions from people who want to know more about this. I’m going to give you a couple of questions that have been asked of us. So this is from a birth worker who says, quote, I am noticing an increase in Rh negative women declining the RhoGAM injection, which we’ll talk about later. I would love to see a review of the evidence on this topic. My sense is that RhoGAM has been routine for so long that the research is probably old. I also wonder if there is any evidence on whether expectant management of the third stage rather than active management and cord traction might reduce the risk of an immune attack against the blood. And, quote, is it reasonable for women who are sure they don’t want more children to decline RhoGAM? Is it reasonable to wait to choose until the blood type of the baby is known? Are there preservatives in the injection that are causing mothers to have concern, and this is why they are refusing treatment? So we’re going to get more into RhoGAM in a minute, but as you can see, this is a really big subject that a lot of people have questions about. 

And I think, Sara, as you and I figured out as we went, that there’s just not a lot of general education on this subject in schools or in life, so people don’t really understand it. So I want to talk about Rh incompatibility in pregnancy. This is the most severe type of blood incompatibility that can occur. And it will only occur if you, as the birthing person, have Rh negative blood. So you have that negative at the end of your blood type. And if you’re exposed to the blood of a fetus, with an Rh positive blood type at some point during pregnancy, this could occur with a miscarriage. It could occur with an abortion, with an amniocentesis, when there is a needle that is put into the abdomen to withdraw amniotic fluid. It could occur if there was a serious fall or a car accident, or it can even occur silently and you don’t even realize it’s happening. 

This is what they call a silent maternal fetal hemorrhage. Where  fetal  blood  passes  through  the  placenta  and  into the mother’s circulation. It only takes a very small amount of fetal blood to trigger an immune response in the pregnant person, sometimes as little as 0.5 milliliters, which is about one-tenth of a teaspoon of liquid. So after being exposed to that Rh positive blood, an Rh negative pregnant person’s body can become sensitized. So being sensitized means that your immune system has been exposed to and now recognizes the Rh positive antigens as a foreign presence in the body. And from then on, the maternal immune system is creating antibodies that recognize fetal Rh positive blood cells as invaders, attacks those blood cells, and destroys them. So if it’s your first pregnancy and this initial exposure is just now taking place, there will likely be no issues with the first pregnancy. The problems start to come in with subsequent pregnancies because now the pregnant person’s body is primed to recognize these positive blood cells as invaders and they can attack those blood cells, causing a potentially deadly complication called hemolytic disease of the newborn or HDN. 

And although about half of the newborns who experience HDN have mild symptoms that require no treatment, the rest are going to have complications that require intensive treatments, such as needing blood transfusions even in utero. Sometimes they’ll do blood transfusions before the birth or after the birth, needing light therapy or phototherapy for jaundice or needing to be on a ventilator. So HDN commonly leads to anemia, jaundice of the baby’s skin, and the sclera in their eyes may turn yellow. It can also cause brain damage, heart failure, stillbirth, or newborn death. And even if you have access to the highest level of care possible, overall mortality rate is 10%. So, 90% survival rate with intensive treatments in the NICU. 

Of course, there are many people around the world who do not have access to NICUs, in which case the mortality rate would be higher. This is one of the main reasons that they test your blood type early in pregnancy. So it’s one of the routine blood draws that around the world, if you do have the ability to have your blood tested for different things, they’re going to test for your blood type. And if they find that you’re Rh negative, they’re going to go ahead and look for antibodies against Rh positive blood. Because it’s possible you may have been exposed and sensitized if you didn’t know you were pregnant before. People may have an early miscarriage and just thought, I have irregular periods and I had a particularly heavy period and they didn’t realize they were having maybe a miscarriage at 12 weeks. So there is a treatment that exists to prevent Rh incompatibility from developing. So we talk about the best cure is prevention. Is that the saying? Sorry, I’m blanking out.

Sara Ailshire – 00:22:36:

No, I mean, it sounds right to me. What is it like? Or was it like an ounce of prevention worth a pound of cure or something?

Dr. Rebecca Dekker – 00:22:42:

Yeah, exactly.

Sara Ailshire – 00:22:43:

The best offense is a defense, I don’t know.

Dr. Rebecca Dekker – 00:22:46:

The best offense is a defense. So the main treatment is focused on preventing the sensitization from taking place to begin with. So what we have is a medication called Anti-D Immune Globulin. I’ll shorten it to Anti-D. The brand name is known as RhoGAM. There’s also Winrho. And this is a medicine that can prevent Rh sensitization. So if you are pregnant, if you’re Rh negative, and you are given this medication, the fact that they’re giving you these antibodies, it temporarily turns off your own body’s immune response. So your body thinks, oh, I don’t need to make antibodies. And so this medicine is actually made from plasma donations of Rh negative donors who did unfortunately experience sensitization. They now produce these antibodies for Rh positive blood. Some of these donors experienced stillbirth or infant loss in their families due to Rh incompatibility. And they’re now donating their antibodies regularly in hopes that they can help other families avoid stillbirth or infant loss. 

And in the US, it’s common for Rh negative pregnant people to receive one dose of Anti-D during pregnancy, one dose postpartum. However, if you are already sensitized, they test your blood. They say you’re negative and you’re already making your own antibodies, there is no treatment available in terms of prevention. Instead, they’re going to be monitoring you closely. So I think the thing to remember about… Rh incompatibility is it’s been going on for a really long time. There were 300 years actually in history where they were documenting babies dying from this condition, but they didn’t know what caused it. I think the first person to describe it in the written literature was a midwife in 1609. And it was a major cause of stillbirth and infant loss for the next 300 years until they finally realized in 1937 what was happening. So somebody said, you know, in that question that was asked to me, is the evidence old? Sort of, but it’s also a relatively in the span of human history, we didn’t have a treatment for this until the last 70 years or so. So Sara, that’s Rh incompatibility. Are there any other incompatibilities that can affect people that we should know about?

Sara Ailshire – 00:25:15:

Absolutely. So there’s one other major type of incompatibility that can impact pregnancy, and that’s ABO incompatibility. ABO incompatibility occurs in approximately 15 to 20% of all pregnancies. And that’s because, you know, ABO blood types are a little bit more widely dispersed than Rh positive, Rh negative. You see a little bit more variety, right? But the important thing to remember about ABO incompatibility is that it causes that hemolytic disease in the newborn or HTN in less than 0.5 to 1% of all pregnancies. So it’s pretty uncommon. It only impacts people who have type O blood, who are pregnant with a fetus, who has type A, B, or AB blood. Another thing that’s different about ABO incompatibility compared to Rh incompatibility is that it’s usually less severe and it primarily presents as jaundice. And as we know, a lot of babies are born with jaundice and sometimes they’re born with jaundice not because anything is wrong. It’s just sort of an artifact of being very immature, having that transition from fetal red blood cells to the more mature red blood cells, their livers kind of coming online. They call it physiological jaundice. It doesn’t mean your baby is in any danger. It doesn’t have this HDN, for example. So that’s one thing that’s kind of important to remember is that like. This type of incompatibility is less severe. It primarily presents as jaundice. And that means that sometimes it doesn’t even get caught. Because the effect is so slight. 

Dr. Rebecca Dekker – 00:26:55:

I do want to just point out, you know, we cover in another episode, we talk about jaundice in more depth. So I’ll link to that in show notes. There’s the physiological jaundice, which is kind of within the realm of normal, but then as the jaundice gets more severe, it can cause life-threatening complications. So I just want to like clarify that. And then this ABO jaundice sounds like it’s kind of in the middle. It’s not necessarily life-threatening, but it’s also not just the normal, gentle kind of jaundice that some newborns experience.

Sara Ailshire – 00:27:26:

Yeah, absolutely. I don’t want to underplay. Jaundice definitely can be severe. It’s just because it’s so common in newborns that sometimes this ABO-linked jaundice gets missed, right?

Dr. Rebecca Dekker – 00:27:36:

Yeah, they don’t realize that that’s the cause.

Sara Ailshire – 00:27:38:

Exactly. This isn’t to say that there haven’t been isolated cases of severe complications due to ABO incompatibility. Those have been documented, but they’re pretty rare. And I think that’s actually why they’re so well-documented, because it’s pretty unexpected. And the doctors, the medical team wants to understand what happened and what was unique about those cases. So another big difference between Rh incompatibility and ABO incompatibility is that there’s no way to prevent ABO sensitization. People who have type O blood are sensitized to A and B antigens throughout their normal life, due to exposure through food, through bacteria, through their environment. Where Rh sensitization is something that can really only occur due to direct exposure to Rh positive blood, either through a pregnancy or, like Rebecca said earlier, if you’ve gotten the wrong type of blood transfusion. Those are the only ways you can be sensitized to that Rh antigen. Because most of the cases of ABO incompatibility are pretty mild, you know, it’s not always caught. And the one time that people will start to investigate, start to say, oh, maybe this is what’s going on, is that if a baby is born with anemia or with severe jaundice, and they know that the birthing person has type O blood, the treatments for ABO hemolytic disease of the newborn or ABO incompatibility are basically the same as what you would see for Rh incompatibility. It’s meant to treat the symptoms. So it can include a blood transfusion. It can include light therapy or phototherapy for severe jaundice and just other treatments that are meant to sort of support their life, keep them going until, you know, the anemia, the effect of that immune attack can resolve itself.

Dr. Rebecca Dekker – 00:29:40:

Okay. So I think that was definitely something really interesting that you and I both learned is about ABO incompatibility because we learned about Rh. But then in the course of our Pro Members asking more good questions, we learned about ABO incompatibility and how it’s not really talked about, mainly because it’s less severe and more rare. But I think the key takeaway is that the Rh incompatibility, is the primary culprit when we’re looking at blood incompatibilities in pregnancy. And again, going back to the whole ancestry conversation, it’s going to be more common or less common depending on what part of the world you’re in. So globally, only 6% of people have Rh negative blood, but the rates are higher in the United States. So around 15% have Rh negative blood, which means if the other contributor to your baby’s DNA has a positive blood type, it’s possible, possible that your baby might have a positive blood type while you have the negative, which can lead to that incompatibility. And another thing I think that people, they still don’t get is that it’s not typically a problem with the first pregnancy. It tends to impact the subsequent pregnancies down the line. And again, before we knew what caused it, there would be a family history of many, many losses and miscarriages, and they didn’t understand why. 

So… moving on, I know, this in general is a fascinating topic, but I wanted to talk about the interesting or surprising things we learned while putting together the resources for our Pro Members on Rh incompatibility. So I’ll start. I’ll go first if that’s okay, Sara. So one of the things that was interesting me is the origins of the term Rh. Why do we call it Rh when it’s the little plus or minus? And you might also hear the term rhesus factor when people are discussing this blood antigen. And what we found is that the reason for this is about 100 years ago when researchers were studying blood, they were using a lot of animal samples of blood, including blood from rhesus macaques. They are like a type of monkey is another kind of general public term for them, rabbits and dogs. And researchers were doing a lot of experiments on blood groups and blood types to determine evolutionary relationships between primates. And researchers understood that clumping when you mix two blood samples was caused by antibodies in one sample binding to the antigens of the other. So in practice, you could figure out the types of blood based on does this blood type clump with this one or not? And they found that with some of the reactions with human blood and animal blood, that there was a pattern of blood types that caused reactions that they had originally found these samples in rhesus monkeys. And so they labeled them Rh positive. And that name stuck, even though later research showed that the human Rh factor is different than the blood factor found in the rhesus macaques. So I think that was an interesting how the name just kind of stuck. And everybody keeps using Rh, even though they don’t know where it came from.

Sara Ailshire – 00:33:11:

Yeah, exactly. You know, and because that rhesus name hung on. That even is the name that they use to describe a whole family of antigens, you know, which the plus and minus is the most common for sure, but it’s not the only one. So it’s just a funny, sticky name that has nothing to do with our blood. And yet here it is all these years later. Yeah. So that is super interesting. One of the things that I found really fascinating and I wasn’t expecting at all in doing research on this topic was that there’s a lot of conspiracy theories that surround Rh negative blood. As part of our work and as part of what we do for our Pro Members, we were trying to understand better why some people may be hesitant to take the anti-D immunoglobulin or RhoGAM shot. And so, you know, to better understand what those hesitations are in order to support our Pro Members and helping to answer those questions for their clients.

Dr. Rebecca Dekker – 00:34:10:

And a lot of those beliefs are things you would expect, like concern about the ingredients or being unsure if it’s effective or… concerns about having an injection, hesitancy. But you found something that I did not expect. What was that?

Sara Ailshire – 00:34:26:

Me neither. And it is that some people have some pretty intense beliefs about what Rh negative blood is or where it comes from. Some people believe, for example, that people who have Rh negative blood are descended from aliens. Which I wasn’t expecting to come across that belief. Another belief that was out there was this new age idea that people who have Rh negative blood are indigo children. So a type of person who has heightened spiritual or supernatural gifts, who is meant to kind of usher us into a new, better age. And some of the people who have these more unique beliefs about Rh negative blood were concerned that the anti-D or the RhoGAM shot would interfere with their alien or supernatural abilities. And in a kind of darker note, some of the people who have these beliefs about Rh negative blood also were proposing that people who have Rh negative blood should only have babies of other people who have Rh negative blood to preserve their special attributes. Which, you know, that was… Again, something that we really weren’t expecting to find. We were expecting sort of the more typical concerns that people have about injections. And we found aliens instead.

Dr. Rebecca Dekker – 00:35:44:

So, and I know that’s not really probably most of our podcast listeners, but I think. Like most people don’t refuse RhoGAM for that reason. But it’s interesting to see some kind of those more drastic fears about the shot kind of trickling down into our subconscious in terms of people thinking that it’s some conspiracy to hurt or harm people. And so I thought, you know, if it’s okay with you, I’ll talk a little bit about, you know, what actually is in the shot. Because some people think that there are toxins in the shot where they link it together with their fears or hesitancies surrounding vaccines. So I want to be clear that Anti-D as a medication, it temporarily suppresses the immune response if you’re Rh negative and you’re pregnant against a potentially Rh-positive fetus. And because this is not permanent, it’s common to receive the shot with every pregnancy or pregnancy and postpartum. It’s given as a shot. It’s not a vaccine. The ingredients are fairly simple. The primary active ingredient is Anti-D Immune Globulin, which is derived from donor plasma. There is salt and water in the injection. There is something called polysorbate-80, which is an emulsifier, which means it helps mix ingredients together and stabilize them. This is also commonly found in ice cream that’s sold in grocery stores. 

And then there is a sugar that helps stabilize the ingredients. And there’s something called glycine that also is a stabilizer that’s commonly added to injectable medications to make it safe to administer via a shot. So Anti-D does not contain thimerosal or other preservatives that are often at the heart of vaccine controversies. It does not include human serum albumin that’s sometimes used in vaccinations. It does not include latex. Yeah, like I said, the ingredients are fairly simple. And the people who do donate the plasma are screened for a variety of conditions. So one of the problems, though, you know, people may think… you know, it’s a vaccine. That might be why they’re hesitant. It’s not. It’s an immune globulin. Some people though might decline it because it’s, you know, derived from blood products, which it does come from plasma, or they may have religious reasons to decline. But I think it’s important to note like that Anti-D, there are shortages of it. There are people around the world who need this medication and can’t get it. So, many people around the world do not have access to Anti-D. It’s estimated that we would need 13 million doses each year around the world to adequately prevent sensitization, but we only have 4 million doses that are administered. And at the time we’re recording this right now in the United States, there is a pretty critical shortage of Anti-D. And so it’s being rationed. It’s typically given in the United States in the third trimester, and then again, postpartum. And in many places, because they can’t get enough doses, they’re only giving it postpartum. And there’s other places around the world where they can’t get it at all. So just something to be aware of. Sara, anything else you learned?

Sara Ailshire – 00:39:06:

Yeah. So something that I was very struck by doing some of this research was learning about Anti-D and the very first people who donated their blood plasma in order to create this treatment. A lot of those people, those early donors were Rh negative pregnant people or Rh negative people who had lost pregnancies. Their first pregnancy went okay. And sometimes they went through multiple, multiple pregnancy losses, miscarriages, stillbirths afterwards. I was pregnant while I was doing a lot of this research for EBB. And I guess that made me feel like just a lot of compassion and awe and appreciation for what those people went through and how they turned their loss, their struggle into a gift to prevent that from happening to other people. There was one woman in Australia who had seven miscarriages, stillbirths due to HDN, and she donated her plasma 500 times in her life before she died. Another woman in Canada had lost two children and had two additional miscarriages. And she donated her plasma so many times that she developed scar tissue in the crooks of her elbows and then kept donating. And sometimes even take a bus to go an hour away. 

If you’re in Australia, you might be familiar with the man with the golden arm. And he’s this gentleman. So this is an interesting example of the other way that the sensitization can happen. When he was a young boy, he had surgery, he got a transfusion of Rh positive blood. He’s Rh negative. And even though, you know, he himself did not bear children, he was very affected by what can happen, these pregnancy losses. And he donated blood, his blood plasma, basically until they had to make him stop. He was, you know, quite old by the time he ceased donating. I think he donated over a thousand times. And these donors are pretty rare. Another thing that I thought was really interesting about this is that . . . RhoGAM or these anti-D treatments have been so successful that now sometimes people who have Rh negative blood have to be sensitized on purpose in order to be able to donate their blood plasma. So these treatments are really effective. They have prevented a lot of suffering and a lot of loss. And sometimes maybe they’re a victim of their own success. It can be hard to find people now who are sensitized in order to get the blood plasma needed to make this medication. So really interesting. I didn’t think about that. Yeah.

Dr. Rebecca Dekker – 00:41:43:

Yeah, very impactful. And I think there’s a picture we shared at the EBB conference of the man with the golden arm with some of the babies and moms around him who had been, lives had been positively impacted by his many donations. Didn’t they have an estimate of like how many people, how many lives he had helped?

Sara Ailshire – 00:42:02:

Yeah, I think so. I think it was from like the Sydney Herald, they estimated, like three million babies saved over the course of his life because with each donation, they can make a lot of the medication. He donated a thousand times and, you know, it’s a pretty common issue in Australia like it is in the U.S. So, yeah, these donors, I think now more recently there is like a young guy. He had been in some type of accident. He got a ton of blood and he’s, you know, he’s younger and he was sensitized and now kind of the man with the golden arm. He can’t do it anymore. And now this young guy is just one example of the new generation of people who’s able to donate their plasma to help make these medications. Also in Australia.

Dr. Rebecca Dekker – 00:42:47:

Yeah, I think that was a really good point you made about like being a victim of its own success, not only in finding these rare donors to create the Anti-D, but also in that families don’t understand like, it’s been, you know, 60 or 70 years since we figured out what’s going on and started working on treatments to prevent it. So people don’t really have those recent memories of family losses and tragedies related to Rh incompatibility. So they kind of don’t appreciate what we have, you know, until now we see these shortages and people are beginning to be impacted or sensitized. And, you know, a few more surprising things. I was wondering if we could talk a little bit about, you know, do you have to be treated with every pregnancy? Some people have said that, well, if I’m not getting pregnant again, I don’t need it postpartum this time. And, Sara, you found some really interesting info and ways of phrasing that. Can you talk about what happens if you’re sensitized and why treatment with each pregnancy is important?

Sara Ailshire – 00:43:56:

Sure, yeah. So, you know. Like we’ve talked about before, this Rh incompatibility can look a lot of different ways. Some people have very mild cases of this, and it doesn’t really seem like that serious or that big of a deal. It’s not guaranteed that each time it’s going to be super, super harmful. But if it is harmful, there’s sort of no going back. This is something where once you’re sensitized, there’s no way to kind of undo that. It’s sort of a lifelong condition that you will have. You’ll be sensitized. It doesn’t harm the sensitized person. It just becomes an issue if they decide to become pregnant again and they’re having pregnancies with a genetic contribution from somebody who has Rh positive blood. So, you know, it can be very difficult to know. You know, what your future holds. And by preventing it, you’re giving yourself the option. And if you don’t prevent it, or if you’re unable to, then, you know, once the sensitization takes place, then that’s all there is to it. Unfortunately, there’s nothing that they can do in order to…

Dr. Rebecca Dekker – 00:45:07:

And sensitization often happens at the birth, which is why they’re offering it postpartum. Yeah. And I also think it’s important for people to remember that … even if you say you’re not planning to have any future pregnancies, not only may you change your mind, but a significant portion of pregnancies are unplanned. So that is something that happens quite frequently in the U.S., so it’s really still going to be best practice for the provider to offer to you, even if you’re not planning on having any more children. It’s still something that they’re going to do because that’s standard care and it’s evidence-based. And we didn’t really go into the evidence on the shot, but we do cover that in the handout for our members. It does lower the likelihood of being sensitized, which we’ve talked about. That’s the main benefit so that in future pregnancies, it can help you carry an Rh positive baby to term. The main risks are mild. So the main side effects include… swelling, tenderness, and pain at the injection site or a slight fever. There have been rare cases of allergic reactions to the human immune globulin that have been reported, but they are rare. So in general, though, it’s considered to be very safe and it reduces the risks of future pregnancies having complications from Rh incompatibility. But we’re still going to see. You know, cases of it being a problem because some people don’t have access to the Anti-D. Maybe it wasn’t administered at the correct time in pregnancy. Maybe you were in an accident and they didn’t give you or offer you the shot. Or maybe you were exposed earlier in your pregnancy and didn’t realize it. And then you find out you’re sensitized. So I would love, you know, to know, post on social media, in the comments on YouTube, wherever you’re listening to this podcast, let us know what are your thoughts on this topic? You know, what’s your number one takeaway? We asked that question at the EBB Conference this past spring, and it was really interesting to see everybody’s thoughts about just understanding blood types, understanding. I think a lot of people were really struck by the man with the golden arm and these donors who have really, you know, just out of the hope of helping others have been providing the immune globulins that make this medication. Sara, any final words you have? I have.

Sara Ailshire – 00:47:29:

Yeah, I mean, I think something that really struck me at the conference, you know, was you have all these people who have all of this knowledge, who are so well versed in all things pregnancy and birth, who were admitting, you know, this was kind of, you know, they benefited a lot from the breakdown, and they were just, you know, feeling like a little bit unsure. So if this is a birth professionals, imagine how people who aren’t in birth world might feel. And, you know, I think something that’s really important is to help people understand, you know, why things are happening. And I think that can oftentimes be a really important way to break down any fears, to help people understand, you know, what is happening? Why is this, you know, being done to me? What is that, the brain or?

Dr. Rebecca Dekker – 00:48:12:

Oh, yeah, benefits, risks, alternatives. What does my intuition say? What if we do nothing? Yeah, just walking down that thought experiment with this.

Sara Ailshire – 00:48:21:

Exactly. Yeah, you know, knowledge, I think, is power. The evidence, you know, can help people understand and appreciate and have a whole picture. And, you know, I was just really struck by how little is out there about something so important like blood. And, you know, I even learned a ton. I think you did too, right, Rebecca?

Dr. Rebecca Dekker – 00:48:41:

Mm-hmm. I did. And I think people are still, even with this evidence, they’re still interested in alternatives. And there are some, I mean, in terms of testing. So some people will like, can I find out my baby’s blood type? Or can I find out my partner’s blood type? So if you are Rh negative and the other genetic contributor to your baby is also Rh negative, then this should not be something you necessarily have to have, right? But if your partner’s blood type is unknown or they have a positive blood type, you can’t know for sure until the baby’s born, after which case sensitization could have happened in pregnancy. So some people are looking at like the fetal non-invasive testing. And then there’s, you know, what is the reliability of that? You know, there’s options that we may have 10 years from now that we don’t have right now, which is good to know. But this is a really complex medical topic. So if you’re, sitting here thinking, I’m still a little confused about parts of this, you can try re-listening to this. We do have a transcript of this available at the blog page associated with this podcast. And, but also we encourage you to go seek guidance from a medical care provider who, you know, has, has provided this shot to clients. If you’re worried about the shot and talk with them about it, do a little bit more reading on the history. I think the history really help me put it in perspective, just like understanding. I think we had a nurse who was a Pro Member. Who’d been a nurse since like the 1970s. And she said, we’re starting to see these cases of hemorrhagic disease of the newborn come back where it was something that, you know, we thought had gone away, but now we’re seeing it more often because of these shortages, because of hesitancy and people being unsure about the RhoGAM. So, she called the Anti-D shot, one of the unsung, like medical discoveries of the past hundred years. It really was a really amazing discovery and it gets a lot of flack now. So hopefully we were able to dispel some myths for you and you learned a lot and we enjoyed sharing this info with you. Thank you, Sara.

Sara Ailshire – 00:51:01:

Thank you. It’s been really fun to talk about this with you again.

Dr. Rebecca Dekker – 00:51:05:

And again, if you want to access the handout, you can learn more about joining the EBB Pro Membership at ebbirth.com/membership. Thank you. We’ll see you next week. Bye. 

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