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Rebroadcast: The little-known virus behind a majority of nongenetic birth defects

WHEAT RIDGE, CO - OCTOBER 31: Megan Nix share a quiet moment with her daughter Anna Wiedel (16 months) at their home October 313, 2016 in Wheat Ridge. Anna has CMV, a virus contracted in utero that caused her to be born deaf. Nix is writing about how CMV is more prevalent than anyone knows, and how doctors are not warning pregnant mothers. (Photo By John Leyba/The Denver Post via Getty Images)
WHEAT RIDGE, CO - OCTOBER 31: Megan Nix share a quiet moment with her daughter Anna Wiedel (16 months) at their home October 313, 2016 in Wheat Ridge. Anna has CMV, a virus contracted in utero that caused her to be born deaf. Nix is writing about how CMV is more prevalent than anyone knows, and how doctors are not warning pregnant mothers. (Photo By John Leyba/The Denver Post via Getty Images)

This rebroadcast originally aired on June 1, 2023.

One virus causes more birth defects in American babies than any other nongenetic disease. But most don’t know it exists.

Megan Nix first learned about congenital CMV when her daughter was diagnosed in 2015.

One in every thousand babies born in the United States will have some symptom or long-term health problem due to congenital CMV.

But most doctors don’t discuss it with expecting mothers during routine prenatal care. Why?

Today, On Point: A mother’s journey to understand her daughter’s diagnosis.


Megan Nix, author of “Remedies for Sorrow: An Extraordinary Child, a Secret Kept from Pregnant Woman, and a Mother’s Pursuit of the Truth.” It’s a memoir about her experience with her daughter Anna, who has congenital CMV.

Dr. Sallie Permar, chair of pediatrics at Weill Cornell Medicine. Physician-in-chief at Komansky Children’s Hospital, New York Presbyterian.

Also Featured

Dr. Gail Demmler-Harrison, professor at Baylor College of Medicine and pediatric infectious disease physician at Texas Children’s Hospital.

Dr. Lynn Yee, medical director of the Northwestern Memorial Hospital Women’s Infectious Disease Program. Associate professor of maternal fetal medicine at Northwestern University’s Feinberg School of Medicine.


MEGHNA CHAKRABARTI: Usually when a baby first enters the world, there’s that life affirming sound of the baby’s cry and the joyous response from parents, family, medical caregivers in the room. But that’s not what happened when Megan Nix gave birth to her daughter, Anna, in 2015. And Megan, in your book, Remedies for Sorrow, you write that something was really different with Anna from the moment she was born. Can you describe the moment of her birth?

MEGAN NIX: She was born at dawn. And so the room was really dimly lit when I gave birth to her. And when the midwife held her up above my body, she was completely silent. And she had dark eyes and dark hair and just stared straight into me. I could tell that she was alive, but she didn’t make any sound at all. And we looked at each other in this suspension of sound until the midwife placed her over my chest, where she breathed but still remained without any kind of scream or cry or anything, until an OB was called.

And she was brought to the corner, to the little baby warming table, and a couple providers huddled around her, jostled her with some towels, and finally she did let out a scream. But her initial silence was a tone that was set for the rest of her life, really. And her silence is something that was much deeper than I realized at the time. Though I felt that there was something really, really different about her and worrisome and mysterious at the same time.

CHAKRABARTI: Yeah, you kind of knew from the start. I understand how that is, that you just have this intuitive connection with your baby from the moment they’re born. What was the midwife’s demeanor when your daughter was born?

NIX: There was a palpable concern in the room, but nobody really said anything. Everybody sort of just looked at Anna, my daughter, for some signal that she was going to be okay. And I started asking, is she okay? Is she okay? And I don’t really remember the midwife’s response, but the doctor said she’s okay, but she’s only 5 pounds and she was full-term. She was 40 weeks. And so, 5 pounds was alarmingly small for a full-term baby.

CHAKRABARTI: You know, I’m thinking back to when my kiddos were born and that first moment where, you know, you’re holding your brand-new baby and you’re seeing how they’re opening their eyes and even though they’re still covered in goop, the smell of the baby and the little yawn they might do, or they might try to latch on. … These are all moments of forming that maternal bond with your child. And you kind of, like I said, intuitively know that all these little actions show that your baby’s here … and okay. Was Anna like that aside from the silence?

NIX: Definitely. Definitely. I held her with awe. And yet there was … I describe it in the book as a gong, kind of ringing inside of me, this alarm bell amidst the love and the intimacy of the moment. There was just this knowledge that there was something else about her that I didn’t understand quite yet.

CHAKRABARTI: And what was that something else? Because you write early in the book that other people noticed that there was something a little bit different about Anna, like the hospital photographer.

NIX: So after we left the delivery room, we then made our way to the mom baby unit, and my parents had purchased an in-house photographer to take pictures. And when the photographer was taking that set, Anna’s eyes never closed. Usually, newborns are so sleepy and they sleep through all the photos. Their eyes are closed.

And for hours she just stared. She just had these clear, dark blue eyes as they lightened from that first moment in the dark room. And she looked out the window. She looked at me. It was like … I might be sort of imposing this upon her and maybe she was just awake, but it seemed like she needed her eyes to see because something else was not in place at that time. And, you know, we later figured out what that was, as we got to know her.

CHAKRABARTI: Yeah. Obviously, we’re going to talk about that in detail and what caused it as well. But I mean, the story really gripped me, Megan, obviously, because I have been through this twice but had a different outcome. But I can intimately relate to all the questions that come about. You know, in the first days and weeks of a new child, a new baby’s life. You write about how your husband actually wasn’t there when Anna was born because he was doing his job, out on a fishing boat. Can you tell us a little bit about that?

NIX: Yeah. So that was also in place in her delivery and in my recovery, was that my husband was not there. He is a fisherman in Alaska in a small town called Sitka, where we live for about a third of the year. And we had decided when I became pregnant with Anna that I would stay behind in Colorado, where we’re from, because I’d had a C-section with my first daughter … and I did not want to fly up to a remote island and either have to have an elective C-section, because I didn’t want to recover from surgery with a husband who fishes seven days a week.

And I wanted just a chance at nonsurgical labor and that I would stay back. And then he would fly home to Colorado when I gave him the call. But the way it works, there’s only, you know, three major flights a day, or four maybe, that leaves Sitka. So we knew that if I called him in the middle of the night, which I did, he would likely miss her birth, which happened at dawn. And then he arrived the next morning. … Her second day of life was when he arrived. And so it was just a charged atmosphere. There was worry. There was his absence. We’re very much a team as parents, and I just needed him to get there. And he did. But when he did arrive, I vocalized to him, and I did over the phone, that something was different about her.

CHAKRABARTI: And what did he say?

NIX: He is a pacifist, so he did not want to initially validate that something might be wrong. But he did say, I told him that she was born small and that she didn’t make a sound. And he said, okay, I want to see her. Don’t worry yet. We don’t know anything yet. And soon we would know everything.

CHAKRABARTI: Yeah. Well, so again, as you write in the book, and as anyone who’s gone through labor and delivery knows, in the day or two after a baby is born, it’s not like a whole piece, right? Like, you don’t get to hold your baby forever and no one bothers you in the room. There’s a lot of testing that’s done on newborns. And so can you describe that to me? Like the normal tests that were done on Anna. And then you write about the doctors that come in and out of the room and you write that they seemed weird. So what was going on?

NIX: So probably the first test that they ran on Anna, is called the newborn dried blood spot, which is where they prick the baby’s heel and then they squeeze out a number of blood drops onto a card at the time. And even with my firstborn, I didn’t know what those diseases were that the blood test would be screening for. And so I just watched in silence without much knowledge. It’s not explained to women.

You just move forward through these sorts of checkpoints after you have a baby. And she was so tiny the nurse could not get her blood out of her heel. And so it just was … everything just sort of seemed more acute with her. And she really had to squeeze out this blood while I waited.

And then after that, the rotating pediatricians from Children’s Hospital came into the room, and there were usually two, there were always two of them for some reason at that hospital, and they would bring her over towards the window and do a physical exam. And they wouldn’t say anything, but they didn’t say anything to me either. It didn’t have the same tone that it had had with my firstborn. There was definitely a perplexity or some kind of, you know, puzzlement about them.

And then the last thing, and this is part of the newborn screening process in all states, is that a hearing technician rolls a cart into the room where they test the newborn’s hearing, and she inserted the wires into Anna’s ears, looking for an instinctual response that the ear makes to sound through the clicks of the wires. And I sat there for a couple minutes and with my firstborn … I didn’t think much about it. … We didn’t have any hearing loss genetically in either of our families, and they handed [my first born] back to me and she passed the test. With Anna, as soon as they put the wires in her ears, I was like, She’s not going to pass. And I waited with this breathlessness until the technician handed her to me and she said, I’m sorry, but she failed on both sides.

CHAKRABARTI: Wow. She actually fell asleep through the test, right?

NIX: She did. Some babies do, because it’s such an instinctual response. They can be asleep, and the test will still register if their ear is, you know, processing sound or not. But she didn’t have any response.

CHAKRABARTI: And how did that hit you?

NIX: At the time, it hit me hard, but I held out this hope that she was small, and the doctors then validated this by saying when babies are born small for their age, small for gestational age, there’s often fluid trapped in the ear and it will drain, and she will pass the next time we run the test.

So the next day, they ran the test again. And again, she did not pass it. And then they said, you will bring her back to the hospital in a week for another test. And so there was sort of this implication that we’ll keep trying until she passes, instead of an acknowledgment that maybe she won’t pass, maybe she doesn’t hear. And inside me, this anxiety just kind of grew and grew like a mass. And I went through each test thinking … her body knows something that we don’t.

CHAKRABARTI: Tell us about how you discovered what was causing a little Anna’s inability to hear.

NIX: So after we left the hospital, we got home and we needed to bring her back for that hearing test a week later, which she didn’t pass. And after that was the pediatrician visit, which usually happens at 14 days of age. We bumped it up to ten days of age because I was flying to Alaska the next day with my daughters and my mom.

Luke already returned to Alaska to continue his fishing season. And so at the pediatrician’s appointment, our doctor … he’s an excellent pediatrician. He held her and he noted her hearing tests in her chart that she hadn’t passed, and her size. And he said, I want to test her for a little known but common virus called CMV. And I said, What does CMV stand for? And he said, Cytomegalovirus.

And I said, I’ve never heard of that. And it sounded just odd. It sounded like there’s no chance, this can’t be common. I would have heard of it before. And we come from a healthy place where I’m educated. I know how to handle pregnancy, seemed like a stretch and I needed to go pack. And I had a raging toddler, you know, kind of pushing, putting pressure on me in the background of everything that I did. And I thought, I don’t need to test her for this. We need to get home. We need to get this fluid out of her ears.

And I said, is the test invasive? And he said, no, it’s just a simple urine catch. And I said, okay, if that’s not going to hurt her and it’s quick, let’s do it. And so a nurse named Susie attached this little pouch to her hips, which she called a potty purse, and the baby pees into the bag and they catch the urine. And so I waited probably 5 minutes, which was great. Sometimes it can take a lot longer. And the test went out to the lab. I asked … if we could still go to Alaska. And he said, Your husband’s there. I know how important it is to be as a whole family. Why don’t you go up there?

We’ll call you. And in the meantime, you can see the pediatrician up there if you need to. So, we flew to Alaska. And actually before that, at home, I started to Google CMV, and I was terrified. The spectrum was haunting and unjust in its array, from asymptomatic to early infant death and almost everything I could think of in between. Deafness, blindness, cerebral palsy, epilepsy, autism, stillbirth. And I had never heard of it. And one thing that really just struck me was the prevalence of it.

I read online that one in 200 babies is born with congenital CMV, and the one in 200 is striking against all of the other things that we know about during pregnancy, like toxoplasmosis, which is the kitty litter disease, affects one in 10,000 babies. And so, I just couldn’t believe that that this was a thing that was prevalent and unvoiced in medicine. And so we got to Alaska. I didn’t get a phone call because it was 4th of July weekend. Monday, I called the doctor’s office and the nurse said, he’s going to call you tonight. And I sort of panicked. And we hung up and she called me back and she said, I need to tell you now. She tested positive for congenital CMV.

CHAKRABARTI: So the numbers that you just presented, that one in 200. The CDC reports that number. Making CMV the largest cause of non-genetic birth defects. So one in 200 babies in this country is born with a CMV infection. But the CDC also says, just to be clear, that of those one in 200 babies, maybe five of them will have some kind of major health impact. So that means that overall, one in 1,000 babies born in this country will have a health impact from CMV. It still makes it the biggest cause of non-genetic birth defects.

CHAKRABARTI: We’re going to talk a bit more about what it is. It’s a virus and the sort of advice and counseling around how obstetricians and midwives should talk with expecting mothers in prenatal visits. But tell me a little bit more. After you discovered this, after you were given that positive diagnosis for CMV, for Anna, I mean, what happened next? It must have been like a complete maelstrom, upending your life almost.

NIX: It was for a long time. It was this storm of emotions and research and confusion and anger, really. When I started researching in the small library in our town, and I realized that the main vector for CMV transmission is toddlers, that one in three toddlers carries cytomegalovirus in their saliva and that 90% of women don’t know CMV exists. I was just totally taken aback and outraged that this had never been mentioned during pregnancy when we are told to avoid, like I said, kitty litter, lunchmeat, sushi, alcohol.

And this risk was right in front of me in a toddler. And some people say that, you know, the first question usually people ask me is, well, how do you avoid a toddler? Well, during prenatal appointments, it should just be as easy as the other things that we avoid, even if we know it’s not possible to totally avoid their saliva. Studies have shown that if women know to use their own toothbrush while pregnant, not finish their toddler’s snacks, kiss them on the top of the head instead of the mouth. Their chances of contracting CMV during pregnancy can be reduced by like 80%.

And just the knowledge that this had not been presented to me, even if I had caught CMV, even if it had happened, I wanted the knowledge. I wanted the honest conversation with an obstetrician during both of my pregnancies, during all of my subsequent pregnancies to where that conversation was absent. And I began to find literature that stated that this knowledge would be too impractical and burdensome for women to handle. That’s the language that the American Congress of Obstetricians and Gynecologists, ACOG uses.

And that just rubbed me as entirely paternalistic to decide for us what we could or couldn’t handle, and to decide for us that ignorance would be better than saving our children from life threatening disabilities or stillbirth. I mean, this knowledge that could save a child was not given.

And so very quickly, I realized that I wanted to read another mother’s journey through this disease, and I couldn’t find one. There was no book. And so I wanted to write the book and I wanted to present this information that was never in front of me. And that clearly wasn’t in front of most of the American population either.

CHAKRABARTI: Yeah. Well, I want to ask you to just hang on here for a little bit, because I’m going to bring in Dr. Sallie Permar into the conversation and the three of us will talk more together about CMV and pregnancy. Dr. Permar is chair of pediatrics at Weill Cornell Medicine.

SALLIE PERMAR: Thank you for having me.

CHAKRABARTI: So give us a little bit of background on CMV or cytomegalovirus. What exactly is it? I mean, it’s a viral infection, but how would we describe what it is?

PERMAR: Yeah. So I describe it as the most common infectious cause of birth defects and brain damage throughout the entire globe. It is a very common virus that most of the world, as adults and even in childhood, acquire. And in underdeveloped regions, most women have the infection before pregnancy. But in more developed regions, about half of women will have the infection prior to pregnancy.

CHAKRABARTI: And in children, not newborns, but in children and adults, how does a CMV infection present?

PERMAR: It’s often asymptomatic. So it’s a virus that many of us carry but don’t ever know when we were infected. It’s one that’s passed very easily with contact with body fluids. So close contact is sort of how it’s best transmitted. It’s also transmitted through breastfeeding, transmitted often by toddlers with how they like to share their fluids and also through sexual activity.

CHAKRABARTI: And so I’m seeing here, this is from the 2015 ACOG guidance that was put out, ACOG again being the American Congress of Obstetrics and Gynecology. And it says that the prevalence of CMV, whether it’s primary or secondary infection, really varies geographically, and actually by socioeconomic status. Like you were talking about a little earlier … it could range from .7% to 4% of pregnant women. Does that make sense to you, that big broad variance?

PERMAR: Yes, it’s very dependent on what one’s exposure risk is during pregnancy. So if you’re someone who lives with many other CMV infected individuals, which is more common in certain geographic areas, it’s more common. In lower socioeconomic status individuals and minorities and in immigrant populations. So those groups are often more exposed to CMV during pregnancy.

However, they may have been more likely to have the infection already before pregnancy and therefore have some immunity. But a really risky time is when a woman has no immunity to CMV before pregnancy and then is exposed for the first time during pregnancy. But often second or third time moms can be in that category because they have toddlers who may have picked it up from other toddlers. And then also people that work with young children like teachers or daycare workers are also highly at risk.

CHAKRABARTI: Yeah. Okay. Now, Megan, I’m going to presume that when you were having your prenatal visits while pregnant with Anna, I mean, you kind of said it, right, that this potential infection, CMV, never came up in conversation. Right?

NIX: Right. Never, never uttered by a doctor. I was never tested for CMV before or during pregnancy, so I don’t know that I had ever contracted it before having Anna. I assume that I contracted a primary case of it because she was born symptomatic, and a primary case will cross the placenta about 3%0 to 40% of the time. Whereas in these other populations that Dr. Permar is talking about, where women generally have already had a CMV infection prior to pregnancy, a reinfection with a new strain will only cross the placenta about 1% of the time.

So like she said, women who have no antibodies to CMV and a toddler at home are at high risk for contracting it. And because most women aren’t tested for it, it’s savvy to assume that you just need to be careful, that you could either never have had it before or you could contract a new strain of it, and either one could end up impacting a fetus. And I wanted to say, just to piggyback on what Dr. Permar said, in terms of CMV being passed through breast milk, bodily fluids, that toddlers are the real risk. And she can correct me if I’m wrong. But like breastfeeding, when you have a child, you cannot give a child congenital CMV by breastfeeding.

Breastfeeding a child who is healthy at birth will never impact them with CMV. Even with Anna, I could breastfeed her and it was very healthy for her, even if it was in my breastmilk, to be breastfed. When that’s a risk is when you have a preemie, and you might have cytomegalovirus in your breastmilk and preemies are fed otherwise in the NICU anyways.

CHAKRABARTI: Okay. So I want to build our understanding about why ACOG does not offer guidance that says talk about this with mothers in prenatal visit. So, Dr. Permar, I’m seeing here, again from this 2015 bulletin, that cytomegalovirus can be detected with viral culture through PCR testing. But that it’s still not recommended, universal screening is not recommended for pregnant women. Why is that?

PERMAR: Yes. So, there’s a lot of work that still needs to be done for good diagnostic tests for CMV. The ones that we have now, especially for pregnancy, are really not adequate to give us all the information you might need in order to determine for sure if a woman has recently had a CMV exposure and that would then put her fetus at risk. Right now, we have the ability to use a serology test or an antibody test that can tell you if a woman has had the infection before pregnancy, or up until the time that you test them.

We can test for the type of antibodies that are more chronic infection, called IgM, antibodies that are more indicative of earlier infection and more recent infection, which is IgG. However, neither are perfect in telling you exactly when … the woman was last infected with CMV. And because unlike rubella, where if you test a woman for rubella immunity, you know for sure she is testing positive, is protected against acquiring that infection and giving it to her fetus, because that is another cause of congenital infections.

But with CMV, even if you have immunity before pregnancy, you could still pass on the virus to the baby. It’s a virus that lives latently within all of us, and you can become reinfected. So, it makes it challenging, even if you do the proper testing, to provide good information. And I think that’s why obstetricians have been hesitant to make strong recommendations. Though in other countries they do use the CMV serology test more often.

CHAKRABARTI: I want to again just dive further into how the American Congress of Obstetrics and Gynecology came about its recommendation to not screen and not discuss CMV with pregnant women.

Dr. Permar, you had mentioned before the break that in other countries, particularly in some European countries, they do regular CMV screening. Indeed, it’s a little difficult to be perfectly diagnostic off of the screening and it’s also difficult to treat. What do they do after the screening? I mean, how did they counsel? Do you know how they counsel women after that in European countries?

PERMAR: Yeah, a little bit there. I would say there are other European countries like Italy and in France and other places where there is more testing of serology used during pregnancy. Like for toxoplasmosis also that we talked about. But I think first and foremost, you can use the serologic testing for conversation about CMV that really, as Megan rightly said as well, a woman who has no immunity to CMV going into pregnancy and especially someone that has toddlers at home, is a high-risk group. In fact, I found myself in that category in my second pregnancy with a child in daycare.

And so I used that information to make sure I avoided my toddler’s fluids throughout my second pregnancy. So I think it can provide counseling in addition to just a way to introduce the risk of CMV for pregnant women. But then also there have been sort of more on the forefront of trying different options. None of them great right now for treating a woman, should it look like she’s had an acute CMV infection during pregnancy. To try to reduce the risk of passing it to the fetus as well as disease in the fetus.

So far, the hyperimmune globulin, something that was one of the earliest therapeutics we used for COVID has been used and really hasn’t worked to prevent or to prevent the infection or prevent disease. And then some antivirals have been used, but those come with some toxicities. And so we’re still really without a great treatment, even if we have the information on the serology.

CHAKRABARTI: We’re going to circle back to that in a second here. But I wanted to just again, just offer people this quote from the 2015 guidance for obstetricians. And it says that the limitations of antibody screening and differentiating primary from recurrent infection, they say, makes it really difficult to use screening in counseling pregnant mothers.

And just as you talked about, Dr. Permar, it says that maternal immunity does not eliminate the possibility of fetal infection. Because 75% of congenital CMV infections worldwide may be due to reactivation of latent virus, which is in a lot of people. And in addition, there’s no proven treatment, which makes ACOG say that further diminishes the potential benefit of universal screening. We can come back to that in a second.

But Megan, I want to play something for you that has to do with what you said earlier about, well, if women were counseled on the existence of this, of CMV as a thing, they ought to consider as they’re going through pregnancy. You know, what would that counseling look like? And could it be something that would lead women to change their behaviors around their toddlers?

Well, as you quoted, the guidance from ACOG says such guidelines may be difficult to implement because they’re considered impractical and burdensome. And ACOG also says at present, patient instruction remains unproven as a method to reduce the risk of congenital CMV infection. Well, we talked to Dr. Lynn Yee. She’s an OB-GYN and medical director of the Northwestern Memorial Hospital Women’s Infectious Disease Program. And she told us she thinks it’s impossible for moms and toddlers to completely protect themselves from CMV.

LYNN YEE: There’s no data that would say that any particular hygiene recommendations are successful at preventing CMV. Versus just living your life as normal. But what I do think is important is that people who are pregnant pay attention to how they’re feeling and their symptoms.

And if you have symptoms, sort of flu like or even COVID like symptoms, seek medical care, not just because it could be seen, but because it could be any number of things that would warrant letting your OB-GYN know about it. Ultimately, I don’t think that there’s enough evidence to suggest we should be doing standardized hygiene education or any other standardized preventive measures for CMV.

CHAKRABARTI: … I want to get a response from both of you on that. But, Megan, you go ahead. You go first.

NIX: Oh, boy. I have so many things to say. First of all, another reason that we need to educate women during pregnancy about CMV is to educate doctors themselves during pregnancies and in the neonatal sphere. Less than 10% of babies are ever diagnosed with CMV who have it.

And so one part of implementing some kind of education program during pregnancy is alerting doctors to the possibility that even if we don’t have accurate data during pregnancy, we should be testing all newborns for CMV in order to treat the ones who are symptomatic and might benefit from antiviral therapy. So when Anna was born, we did have the good fortune of testing her within the necessary time frame.

You have to test a baby for CMV before they’re one month old, because otherwise they could have contracted CMV as a cold from a toddler in the house and are fine with it. And we don’t want parents, you know, freaking out that they had congenital CMV when it’s just a postnatal contraction. So you have to test newborns for it and get them on an antiviral before it is a false positive. So that’s another reason for education during pregnancy of both women and their doctors.

NIX: … We do not have great larger studies to prove that hygienic precautions are successful to the extent that we want them to be during pregnancy. But medicine works on supply and demand.

And so if we are not demanding bigger studies, more pregnant participants, to see if these measures do work, then doctors continue to cause CMV, something that we shouldn’t worry about. It is the leading cause of infectious birth defects. And if we are saving one woman from a stillborn child because she understands where it is, and probably way more than that, CMV is the leading pathogen linked to stillbirth. We need to be talking about it. We need to be looking at solutions. And even if those solutions aren’t perfect right now, you know, Dr. Marc Salita is a doctor in Minnesota who I quote in the book.

And testing newborns is also complicated. The whole package is complicated. That doesn’t mean we just put it under the rug. He says that, Why let the perfect be the enemy of the good? We don’t have all the right answers now, but in ten years we might. And so, you know, to just stop the train and say we can’t do anything about this enables the medical industry to not do anything about it. And meanwhile, children are being born severely disabled with life threatening challenges.

CHAKRABARTI: So we’re hearing kind of a wide spectrum of interpretations of studies. And to Megan’s point, there actually aren’t that many on that happen during pregnancy to begin with. We’ll come back to that in a second. But regarding what happens when a woman is counseled about potential CMV infections from their toddlers and potential for behavior change, then what does the evidence base say? I mean, it’s hard for me to sort of figure out, like the ACOG says no good. But Megan quoted another study that says there’s a 70 to 80% change.

PERMAR: So I think what you’re seeing is that the studies that have not all had the same results. And therefore, it’s kind of open to interpretation. And so physicians and obstetricians in some European countries are interpreting the data differently than really our at least the established U.S. ACOG guidelines. And I think the one of the really, I think tangible things that can tell you that behavior change can change acquisition of CMV risk is if you think about hospitals where we have lots of patients that have CMV, lots of patients that have immune compromising conditions, that leads you to be more at risk of CMV disease and shedding the virus often. But there’s never been nosocomial transmission of CMV reported, and essentially that’s because of universal precautions.

Anytime you’re going to come in contact with bodily fluids of a patient, it’s required to wear gloves. There’s lots of hand-washing and we’re audited on that, and that can reduce the risk. So I think, you know, think about nosocomial transmission in hospitals really shows that behavior change can work.

CHAKRABARTI: Well, one thing that there seems to be a lot of agreement on here is that there’s an inadequate evidence base, let’s say, regarding infectious diseases in pregnancy to begin with. And so I want to once again just hear quickly from Dr. Lynn Yee. She’s at Northwestern Memorial Hospital. And here’s what she said. She believes that funding, more funding needs to be dedicated for pregnancy research in general.

YEE: By excluding pregnant people from research on potential diagnostic or therapeutic strategies, we are affecting the whole family unit and not generating evidence fast enough on how to give the best possible care to the pregnant person. And we’ve seen this time and time again. You know, other diseases, infectious diseases, show the same thing. Hepatitis C, for example, the research in pregnant people is a decade behind the research in non-pregnant people. CMV, the research on creating a vaccine is far behind where technologically we potentially should be.

I think that as a scientific community, what should change is greater attention and prioritization of pregnancy as an important period for research.

CHAKRABARTI: That’s Dr. Lynn Yee at Northwestern Memorial Hospital. Now, a little bit earlier, Megan, you used a really kind of key word about paternalistic in terms of the guidance that ACOG has given out. That’s a word that Dr. Gail Demmler-Harrison also uses. She’s a pediatric infectious disease doctor at Texas Children’s Hospital, and she says that not giving the CMV guidance to women is paternalistic. And in her view, … she wants the American Congress of Obstetricians and Gynecologists to revisit their guidelines.

DEMMLER-HARRISON: I think it would be totally reasonable to throw into the bag that pregnant people get when they are told they’re pregnant. Something about CMV. A pamphlet, you know, just like you’re told about, you know, lunch meats, kitty litter, travel to certain places. The other thing that I think, which it’s not the most popular opinion is that adding a CMV IgG antibody to the prenatal screening would be simple. It starts the conversation about what is CMV? Oh, well, you’ve never had it. Well, try and stay that way. Oh, you’ve had it, but you can be re-infected. And here are some ways.

CHAKRABARTI: Doctor Permar, just really briefly, we could do a whole show on this, but really briefly, who writes the guidance? Right? I mean, if we’re talking about this word paternalistic keeps coming up, but there’s this huge body of data that whoever writes the guidance has to take a look at. I mean, how do these conclusions get made, which then are spread to, you know, every obstetrician in the United States.

PERMAR: Yeah, Representatives that join committees from the obstetrics field would review these guidelines. And it takes years often to review these guidelines and new data is reviewed, which again goes back to that we don’t have enough data or studies that are informing them.

CHAKRABARTI: Well, we’re really getting close to the end of the program here, unfortunately. Just got a couple of minutes left. Megan, there’s nothing stopping women right now who’ve heard this program to go into their next, you know, prenatal visit and ask about CMV. I mean, it sounds like this is something that if change is going to happen, it may have to come from patients themselves.

NIX: Right. I think that’s a good way to establish that we do care. And other studies aside from testing during pregnancy, when women are surveyed in both the U.S. and Italy, 90% of women or more want to know about CMV. And equal numbers will implement these hygienic precautions to provide the healthiest possible environment for their pregnancy.

And so I think the more that we have this conversation, and the more women are given the latitude to make this decision for themselves. Do I want to worry about this? Do I want to avoid my toddler’s saliva, or do I want to say, you know, this isn’t a big concern for me, Then the better our situation is as people who are in a system of informed consent.

And I think that, you know, my book lays this out. This is not simple. And yet women having children are willing to take on complexity. They’re willing to take on challenge. And my book is researched and complex. And I think that people need to know all of the details about CMV to understand the real possibilities of any pregnancy, that we do not live in a zero-risk environment and our children might be disabled. And that is a beautiful thing in many ways. But when we are subjecting them to life threatening challenges, that is something that we should be preventing.

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