Thinking About Ob/Gyn
A fresh and evidence-based perspective of all things related to obstetrics and gynecology. Follow us on Instagram @thinkingaboutobgyn or visit thinkingaboutobgyn.com for show notes and more.
Thinking About Ob/Gyn
Episode 11.10 New Guidelines For Cervical Cancer Screening and More!
Use Left/Right to seek, Home/End to jump to start or end. Hold shift to jump forward or backward.
We bring back the biggest takeaways from the ACOG ACSM, then move fast through the newest guidance and the newest hype shaping real OBGYN care. We focus on what the evidence actually supports, where practice still lags behind, and how “labels” can quietly push patients toward harm.
• conference highlights including rural OBGYN access and what gets attention on the exhibit floor
• vitamin K shot refusal trends and why late bleeding still matters weeks after birth
• 2026 ACOG cervical cancer screening changes with primary HPV testing preferred for ages 30 to 65
• self-collected HPV screening and the systems needed to keep follow-up safe
• why annual Pap testing and cytology-only strategies increase overdiagnosis and can miss HPV risk
• postmenopausal bleeding workup shifting toward ultrasound plus endometrial biopsy up front
• large baby induction data and why outcomes can worsen without neonatal benefit
• third-trimester ultrasound screening performance and the real-world labeling effect
• early proof-of-concept therapy for preeclampsia targeting sFlt1 removal to prolong pregnancy
• hysterectomy duration and route as drivers of venous thromboembolism risk
• laboring down claims from retrospective reports versus randomized trial findings
• debunking physiologic third stage claims and reaffirming active management to prevent hemorrhage
Be sure to check out thinkingaboutobgyn.com for more information, and be sure to follow us on Instagram.
0:00 ACOG Meeting Takeaways And Rural Access
3:58 Vitamin K Refusal And Newborn Bleeding
6:37 Cervical Screening Moves Toward HPV
14:48 Postmenopausal Bleeding Now Needs Biopsy
20:00 Tylenol Data And Macrosomia Induction
28:34 Ultrasound Labeling Effect And Liability Fears
37:29 Removing sFlt1 To Buy Time
40:14 Longer Hysterectomy Surgeries Raise VTE Risk
42:14 Laboring Down Claims Versus RCT Reality
49:59 Counseling Fatigue Without Ignoring Risk
54:21 Third Stage Myths And Hemorrhage Prevention
58:42 Evidence Literacy And Closing Notes
Follow us on Instagram @thinkingaboutobgyn.
ACOG Meeting Takeaways And Rural Access
SPEAKER_01Welcome to Thinking About OBGYN. Today's episode features Howard Harrell and Antonia Roberts discussing new guidelines and more.
SPEAKER_02Howard?
SPEAKER_00Antonia?
SPEAKER_02What are we thinking about on today's episode?
SPEAKER_00Well, we just got back from the ACOG Annual Clinical and Scientific Meeting in Washington, D.C., and we were both able to attend the 75th anniversary ABOG Foundation Gala, and you snuck in an extra passenger to the gala and also to see Michelle Obama give the keynote speech, which was a hard ticket to come by too.
SPEAKER_02Yeah, I guess we were a little sneaky, but it was fully legitimate. My baby had her own badge and everything. So I don't know if she wants to go into OB yet, but I think she's shown some interest. So I'm just letting her get her feet wet.
SPEAKER_00She's already four months old. She should know by now what she wants to do with her life.
SPEAKER_02Yeah, she's a go-getter and she's very good listener at all the talks. I think anyone that met us there would say she's a great conversationalist, great networker. And I think the keynote speech really was directed at her, probably as much as anyone else in the audience.
SPEAKER_00We can all use a pep talk every now and again, I guess. I also think it's safe to say that Michelle Obama and the new ACORG president, Dr. Camille Clare, definitely delivered in that pep talk department. So I'm also happy to announce personally that Dr. Clare's presidential initiative will focus on rural Obigemian access, and I've been asked to work on that project with her.
SPEAKER_02Yeah, that was really great to hear her talking about that. It's obviously we've talked about it here so much. It's one of the biggest problems we face in our profession right now and really needs all hands on deck. So I'm glad it's getting that level of recognition in ACOG. So did you have any other favorite takeaways from the conference?
SPEAKER_00Well, there were lots of things. There was another one of the large general talks was about how AI is changing or will potentially change healthcare, specifically in OBGYN. And it's a lot more than you might think. It's more than just generating patient notes and dictation. But I'll refrain from going into that too much because I could probably take the whole hour just talking about that. And we are going to talk in the next episode, our guest hosts, about how AI is going to transform medicine on a very basic level. So we'll get back to that topic. But what about you?
SPEAKER_02Well, that yeah, that sounds exciting. I didn't go to that talk. I always go to the surgical tutorials just for a good refresher. They had some good ones again this time. And nometriosis surgery and deeply impacted fetal head during cesarean, and both of the rooms were totally packed, and I think had overflow rooms going.
SPEAKER_00Oh, and the speaker for deeply impacted fetal head is going to be on the podcast as a guest host soon.
SPEAKER_02So my goodness. We've got we've just got such high levels.
SPEAKER_00All the celebrities. Yeah.
SPEAKER_02Yeah. I know we we both went through the exhibit hall, which was a circus in and of itself. Some some good stuff and some amusing stuff, some supplements that I don't know if maybe just take them with a grain of salt, but they're the folks that I guess pay for a lot of the conference. So kind of just have to take that for what it's worth. As far as other talks, I really loved the U.S. Preventative Services Task Force endowed lecture. So I think that's a recurring talk every year. This year they hit on recommendations for screening intimate partner violence, perinatal depression, for supporting breastfeeding, screening syphilis, which we've talked about recently, and also changes for cervical cancer screening. And I think that last part, the cervical cancer screening, generated really the most question and answers of that whole session.
SPEAKER_00Yeah, we'll definitely have to talk about that, those changes a little bit on this episode. So there's a lot to keep up with. And I think we can at least get to the cervical cancer stuff. So let's do some quick hits from the journals, too, that we so we don't get too far behind on new and exciting literature.
Vitamin K Refusal And Newborn Bleeding
SPEAKER_02We'll start then. So I'll elevate this piece from ProPublica from May 6th, 2026, called Babies Are Bleeding to Death as Parents Reject Vitamin Shock Given at Birth. This article is a 20-minute listen or read. They tend to really go in depth with their pieces. And it puts a human element on this really, I think, unfortunate trend and gives some concrete numbers too. They have a graph that shows the percentage of newborns not receiving vitamin K, and that's it's been steadily increasing since 2017. Now it's over 5% of newborns. And the article also highlights that some of the deaths and complications from bleeds that happened occur weeks after delivery. So even at with about 95% of kids still getting the shot, there's about 700 newborns each year that die from spontaneous bleeding in their brains. And so with the rate of vitamin K refusal increasing, that that number is likely to get dramatically worse.
SPEAKER_00Right. And not all of those 700 or so newborn deaths, of course, would have been saved by the vitamin K shot. Many of those infants obviously still receive vitamin K and had traumatic deliveries or other problems. But as that 5% of newborns who's not getting the vitamin K shot, as that number increases, it's not unreasonable to think that the number of deaths will go up substantially. It it probably won't be a tenfold increase, let's say if it goes from five to fifty percent. But it's reasonable to think that it could double or triple easily if we start seeing very high refusal rates in some of our communities.
SPEAKER_02Well, I hope you send this article to your pseudonym friend Anna. But you you had a recent episode with her, I think the vaccination episode, and you had talked about there, it's not just deaths that you prevent with these preventative routine measures like vitamin K. For every child that dies, there's several others who live with permanent disability after having uh basically a hemorrhagic stroke. For newborns who don't get vitamin K, the risk of a serious bleed like that, it's still rare. It's about one in 14,000 or so. But if they do get the shot, their risk drops down to one in a hundred thousand.
Cervical Screening Moves Toward HPV
SPEAKER_00Yeah, so like a six-fold decreased risk, if you think about that across the population where we have almost four million births a year. So I'll have to send that to Anna and see what she has to say. Okay. Well, the next quick hit, we should review what you mentioned, the changes to our Papsmere guidelines. So there's a new committee statement on screening for cervical cancer that came out April 24th, 2026, and this gets ACOG almost caught up essentially with the rest of the world and with other professional societies.
SPEAKER_02Yeah, so this is what they were talking about at the one session I went to, and I think there was at least another whole session at the annual meeting just dedicated to the PAP screening changes. So it's a pretty comprehensive change, I'd say. And of unfortunately, the truth is most people still aren't even following the prior updates to the guidelines. They're still stuck on 20 years ago or longer, just basically doing annual PAPs on everyone, starting from when they first start being sexually active. So that's a knowledge to action gap like we talk about a lot. The ACOG statement here isn't exactly like the other guidelines, but it does start to shift more towards reliance on HPV only. So let's go over some of the details.
SPEAKER_00Okay, patients 21 to 29 should still get cytology alone, according to this recommendation, every three years. So that's the same thing if they have baseline risk and have had normal results. So that is different than other guidelines that use HPV-only screening starting at age 25. But then after that, patients who are 30 to 65 should have a primary high-risk HPV screening every five years collected by the clinician. So no cytology. The guideline does allow for self-collected tests every three years with an FDA-approved kit when systems are in place to make that more feasible and make sure follow-up's taken care of and everything like that. So that's a work in progress, but we'll see that more and more. The co-testing that we've traditionally been doing between ages 30 and 65 is still considered acceptable when primary testing is not available, or if the patient chooses it after being counseled appropriately. But primary HPV screening is now preferred.
SPEAKER_02Yeah, and and that'll be interesting. That that's really never been done before for cervical cancer for a lot of us. So of course, clinicians who are lax on catching up with new guidelines will they'll be uncomfortable with these changes and they'll try to maybe appeal to patient autonomy. So I imagine many practices, at least for the next several years, will just try to claim that the patient chose to keep doing whatever they were already doing, be that co-testing or even the annual PAPs after counseling. And and in some ways I would believe that because I s we both see people that have been used to getting annual PAPs and expect that they're supposed to get annual PAPs. But the counseling could be heavily suggestive and biased, like basically the doctors telling them something along the lines of more testing is better or better safe than sorry, when what they really should be saying is cytology screening is less accurate and may lead to more harm.
SPEAKER_00Right. And the idea too that obviously if you're doing co-testing, you're doing cytology plus the HPV. So people will struggle with that of why are we, if I'm doing this every five years and I'm putting a speculum in, why wouldn't I also get the cells? Why would I just get the virus? It because that's essentially what they're being asked to do. So I think that'll be hard for people to wrap their head around that getting the cells is actually harmful. And we can talk about that in more detail, but the viral screening is way more sensitive and more specific, and the cytology, if anything, just detracts from that, especially when you get abnormal cells with negative HPV. So we can talk about that more in detail. But they do strengthen the idea that cytology alone is not appropriate at ages 30 and up. Although, again, they say if the patient chooses it after counseling, then it's essentially better than nothing. I still see quite a few clinicians who do PAPS cytology every three years without co-testing. And they believe they're following the old guideline while still getting to do a test more than once every five years on the patient. But actually they're, again, they're harming the patient when they do this because the HPV screening is so much better. Even the old guideline didn't really support the idea that cytology every three years was an equal alternative to co-esting every five, but the new guideline does go a step further and says that it's only appropriate when either primary HPV testing or co-testing are not available. And of course, that would be an incredibly unusual circumstance, at least in the United States.
SPEAKER_02Yeah. And I think another ill-informed excuse for doing it that way, besides that it's just habit, is assuming that insurance will not pay for the HPV part of the testing, whether that's primary HPV screening or co-testing, especially co-testing if the cytology is normal. And I don't even know if that's ever been true, but certainly at this point, it really should not be true anymore with the way the guidelines have changed. ACOG does also, with this new update, reaffirm we should still stop screening at age 65 for average risk patients as long as they've had three consecutive negative cytologies or two consecutive negative co-tests within 10 years before stopping screening. Or now if we're switching to primary HPV, two consecutive negative HPV tests. Of course, it also stops for patients at any age if they've had a hysterectomy without prior high-grade precancerous lesions, too.
SPEAKER_00Well, the exciting thing we've talked about here before could be the self-collecting tests, the self-collected test. So they're finally incorporating that into our formal guidelines. And there should be implemented as soon as you have resources to do it, at least offered to patients. So there are a few caveats that mainly relate to the ability to do reflex testing on abnormal results, so they'd have to come in for that. So people definitely should read the specifics, but self-collection, of course, won't be completely equivalent to the traditional specimen collection that's done with a speculum, and that's why it's every three years instead of five. But it hopefully opens up access for a lot of patients who otherwise wouldn't be getting screening. The other main discrepancy here with other international guidelines is for younger women, arguably, where we've had less HPV vaccination in the United States, we might be exposing younger women to more invasive testing if we did this HPV screening on them in their 20s, whereas in Australia or something, it may go the other way. So I think that's the main concern about not adopting HPV screening starting at age 25. The document doesn't really elaborate why they didn't go all the way, but it does acknowledge that the American Cancer Society includes primary HPV screening as an option for patients age 25 to 29, essentially into the word, starting every five years at age 25 for physician-collected HPV testing. And that's what's done in Europe and other places, but again, we've had less uptake of the cardicil vaccine here.
SPEAKER_02Well, if anyone out there is still doing yearly PAPs, especially cytology only, then they're about a quarter century behind and literally are harming their patients with the decreased accuracy of it. For a big group of patients, that's gonna really mean increased risks and distress of overdiagnosis and unnecessary biopsies or other procedures. But then even for another group of patients, they may be underdiagnosing when they're not checking HPV, because people very well can have normal cells and HPV 16. And then if you're not picking that up appropriately, then you know that you could actually lead to missing a cancer. I doubt any of those are our listeners, but if you are, then read the new guidelines. Get up to date.
Postmenopausal Bleeding Now Needs Biopsy
SPEAKER_00Well, 10 days before that bulletin came out, we had another big update that affects our everyday practice. So on April 16th, there was an ACOG clinical practice update on the role of transvaginal ultrasound in evaluating the endometrium for patients with postmenopausal bleeding.
SPEAKER_02Yeah, we've talked about this issue before too, and uh you could probably see this coming. Endometrial cancer is on the rise compared to other female cancers. And 90% of patients with endometrial cancer present with postmenopausal bleeding. So for the longest time, what what was drilled into me and probably you too in training was start with a transvaginal ultrasound and then only do a biopsy if the endometrium is thicker than four millimeters, because traditionally that four millimeter cutoff gave a negative predictive value of about 99%, at least in the past. So then you would only biopsy patients up front with a thicker endometrium or with significant risk factors like family history or obesity or things like that. And we also mentioned before that data shows that for black women, especially, there's lower sensitivity of ultrasound, meaning more of them will still have cancer even with a thin lining. But now the new recommendation is that patients with postmenopausal bleeding up front will get both a transvaginal ultrasound and an endometrial biopsy as an initial step. So they they do say that ultrasound without biopsy might still be used carefully in a few select patients. Maybe they've had one single episode of bleeding. The ultrasound is perfect quality with a very thin endometrium, no other risk factors. But even for them, if they have a single recurrence, they should still get a biopsy. And then you might wonder like, why even get the ultrasound? If it shows focal lesions, that that would prompt you more to say, maybe we still need to go do a DNC, even if we have a benign biopsy.
SPEAKER_00Right. And other, obviously, other anatomic causes of bleeding that might affect any age group. So I like this change. For one, we were leaving it up to clinicians to go through and think about whether someone had these risk factors or had certain ultrasound features that would push you to do a biopsy. And so undoubtedly patients who should have gotten biopsied were being missed. But two, we moved away from race-based guidelines a few years ago. So we were never going to really adopt a specific guideline that included race as a reason to do a biopsy apart from other factors. So they did include in the table in that document a list of risk factors for endometrial cancer that should have pushed your thinking towards a biopsy, including exogenous estrogen use, using a CERM, obesity, noliparity, a genetic predisposition to endometrial cancer like Lynch syndrome or something, black race, diabetes, et cetera. And if you think about that, that's going to be a sizable majority of the patients who present with bleeding anyway, so most people are probably going to have a risk factor. But people were likely missing some of these. And so it still allows us to not biopsy every single patient, potentially unnecessarily. Just last week, I, for example, I had a patient whose bleeding started after initiation of a blood thinner. Her ultrasound showed a very well-visualized one millimeter lining on a tiny postmenopausal uterus. And I chose not to biopsy her. She didn't have any other risk factors. But of course, if she comes back with more bleeding, then I will. So these new guidelines support that sort of care where you can still individualize it for some patients. And hopefully that'll cut down, though, on delayed diagnosis in MIST cases for people who should have been biopsied and weren't.
SPEAKER_02I do wonder if it'll lead to more DNCs, because there's a lot of patients that can't tolerate office biopsy.
SPEAKER_00Yeah, that was always a trade-off, and especially with thickening that's not associated with bleeding, asymptomatic thickening, those patients are more likely to have cervical stenosis. And a debate about how many millimeters you should be before you get a biopsy is largely predicated both on what's the possibility of finding something, but also how many patients get pushed towards a DNC either in the office or in the hot in the hospital just because of an instinct finding on radiology. And so with patients at least who've been bleeding, most of them are not going to be so stenotic that you can't do a biopsy, hopefully.
SPEAKER_02Yeah. And one of the effects that would tend to happen when patients have a normal ultrasound after presenting with bleeding is they could be falsely reassured that, okay, I'm in the clear. And then they may go on to ignore bleeding for quite a bit afterwards. And then let's say a year later they present with persistent bleeding and turn out to have a higher stage of cancer than they had a year ago if they had just been biopsied a year earlier. So ideally, patients will receive an ultrasound anti biopsy ideally the same day that they present for postmenopausal bleeding.
SPEAKER_00Okay, so those are two big changes to practice.
SPEAKER_02Yeah. And just to follow up again on another episode we previously had about acetaminophen exposure and the risk of autism, as if we needed any more data, there's a study published in GMF Pediatrics recently that looked over one and a half million children born between 1997 and 2022. And they found that autism was later diagnosed in 1.8% of the children exposed to Tylenol in utero and 3% of the unexposed group. So almost half the rate of autism with the Tylenol exposure, actually. And this lack of association persisted after doing all sorts of different controls in the data. And it's also similar to a Swedish study from 2024 that we've already discussed in the past.
SPEAKER_00So that sounds like Tylenol might be protective against autism.
SPEAKER_02One of us should call up RFK and let him know. I'm the one that has an autistic kid when I didn't take any Tylenol. So maybe I'll have him call RFK.
SPEAKER_00Well, or maybe we should just be careful to make associations or make causation implications from associative data, regardless of whether it favors our pre-existing beliefs. So okay, well, we can draw straws on that one later. How about a couple more quick articles first? There was an article published in the April in April 27th in BMC pregnancy and childbirth on mode of delivery for confirmed macrosomic babies. So this was a retrospective multi-center study at three French hospitals between 2017 and 2023, and they included term women who were known to have pregnancy with suspected fetal weights of at least 4,000 grams. So they wanted to look at basically the idea of induction, maybe even as early as 37 weeks, and see what the outcomes would look like. Overall, the average gestational agent induction was still 40 weeks and two days compared with the expectantly managed group, which averaged 40 and 4. So that wasn't like we're going. Now, of course, this is retrospective data, but they looked at the mode of delivery with secondary outcomes including risk of hemorrhage, perineal tears, obviously neonatal morbidities and mortalities. And they looked over 76,000 deliveries and found 4300 that made inclusion. And of those roughly 1,800 were inductions and 2,500 were spontaneous labors. What they found was that induction was associated with a higher cesarean rate of 45% versus 10%, and an increased risk of postpartum hemorrhage at 27% versus 15%. Importantly, there were no differences observed in the risk of low apgar scores, shoulder dystocias, or adverse neonatal blood gases.
SPEAKER_02That is quite a striking difference. You have to wonder how induction increase those risks so much. But I'm glad that they did this study. We are classically taught that third trimester babies gain about a half pound a week, or roughly, which is roughly 250 grams a week. And obviously this can be variable. I've seen a few large babies who, at 39 weeks, when they were born, weighed the same as what their ultrasound had estimated them to be three weeks earlier. So either they didn't gain it any extra weight or the ultrasound was just that off. So it's quite variable. I cannot find a paper specifically on average fetal growth week by week with macrosomic babies. So I don't know if that follows maybe a different trajectory or what. But in this paper, the women who were induced, so that that included all comers week by week. There was some at 37, some at 38, 39, 40. So on average, any of them that were induced because of this macrosomia, the babies weighed on average 42, 64 grams, whereas the ones who were allowed to wait to spontaneous labor weighed an average of 42, 80 grams. And as you said, the average gestational age ages were about two days different. So they're 16 grams different. Everyone can probably imagine that's not gonna do much. So it makes sense why outcomes at least were not better between the two groups. It really doesn't explain why outcomes were worse necessarily. I also didn't see a breakdown here of fetal weights by week or shoulder dystocia rates by week, but they did show week by week the C-section rate. And the 37-week induction group had the highest C-section risk compared with all the rest of the patients, including the ones that were induced at 38, 39, etc., as well as everyone who just waited for spontaneous labor. So obviously those babies would have had to weigh the least, you would think, and they still had the highest C-section rate. So that kind of shows you that just having a lower weight baby doesn't necessarily make all the difference. And and it suggests that even if the study had had done every all the inductions for macrosomia, do them all at 37 weeks, don't wait any later, and then compare all of them to people who just went into labor spontaneously, then that still would likely not have been much better, even if the baby weights had been less. So the authors of this paper did also reference a randomized trial in their introduction called the Dame study that had reported improved outcomes with early induction for macrosomia, but that was in conflict with other studies in the past that have not confirmed those findings. So unfortunately, this study adds weight to the conclusion that early induction does not improve outcomes for macrosomia. It only significantly increases the rate of C-section. And obviously, we all worry about shoulder dysocia when someone has a huge baby, and we would love for some reliable way to reduce that risk, but early induction just isn't it. Now, I think there may be some nuance potentially between early elective induction for just macrosomia versus early induction for poorly controlled noncompliant diabetes. I have seen a case or two where the MFM will recommend 37-week induction for a diabetic patient that's has a very macrosomic infant. And I've seen that at 37 weeks they are over 4,000 grams. But that's not what they were looking at in this study. So outside of diabetes and those kinds of consideration, I I suppose let's say someone's 39 weeks and they have a favorable cervix and otherwise meet some sensible indications for elective induction or even some other medical reasons, you could reasonably offer induction anyway. And that's still fine. They're definitely not discouraging that. But the size of the baby alone is probably not a good reason.
SPEAKER_00Yeah, I think that if there's any speculation about why the rates of hemorrhage and cesarean were higher, it's just that a lot of these patients were not ready for induction.
SPEAKER_02Yeah.
SPEAKER_00Their cervix was run favorable, they had more oxytocin exposure, which is a surrogate for they had not as developed oxytocin receptor response in in the myometrium, and so they were more likely to have hemorrhage and they were more likely to get sectioned. And of course, we're used to now talking about things like the arrive trial, where we've kind of given up on the idea that induction increases the rate of cesarean, but most of the world's literature shows that it does, particularly in patients who aren't prepared for induction, especially when you get into 37 weeks or 38 weeks rather than 39 weeks. But also, even if you want to buy into the idea that inductions done well shouldn't result in more cesareans, there's also this idea of the labeling effect, where these patients were being induced for macrosomia, and so people are ready to take that off-ramp whenever they get a moment. And so the propensity towards cesarean might be higher in a population of women who've been labeled as having huge babies, and that's why we're inducing you at 37 weeks. Whereas the women who were just allowed to labor on their own maybe didn't have the same labeling effect problem. I don't know.
Ultrasound Labeling Effect And Liability Fears
SPEAKER_02Well, speaking of that very thing, there's an article in the April 2026 Grade Journal that looks at that. And specifically, they're looking at screening for large for gestational age infants at term or fetuses at term. So I thought you'd like this one.
SPEAKER_00I do like this one. So let me read the subtitle. Evidence of a labeling effect. This is where I got the idea, right? And increased intervention without neonatal benefit. So I think these two articles are very much related, and this labeling effect is important to understand both of them. So this is another retrospective cohort of nearly 22,000 pregnancies who underwent routine 35 to 37 week ultrasound. And then those that were greater than the 90th percentile were defined as screen positive for LGA or large registral age. And this corresponds, in theory, roughly to those babies born who weigh about 4,000 grams at birth, which we call macrosomic. So they too collected data about mode of delivery and composite adverse perinatal outcomes that included maternal and neonatal outcomes, of course. And so all the usual things which you can imagine, it's a long list. But the first thing is that you were talking about ultrasound before. Well, ultrasound screening for macrosomia showed a sensitivity of only 34.9% for large registrational age, I should say, and 35.6% for macrosomia, with a specificity of 97.4% and 95.6%, respectively.
SPEAKER_02So that's a pretty bad test.
SPEAKER_00It is. And we have way too much confidence in the ability of ultrasound at term to identify reliably large for gestational age infants. It's an unreliable test, particularly if you don't have sufficient pretest probability. And so if your goal is defining which babies in a general population are going to be large for gestational age, and you're looking at a lot of normal risk patients, those without gestational diabetes or excessive maternal weight gain, someone for whom you wouldn't normally be getting a growth ultrasound, it becomes an increasingly unreliable test. But among those that were screened positive, those patients were less likely to attempt labor to begin with, in other words, just go straight to cesarean, more likely to undergo an intrapartum caesarean delivery after labor or induction started, and they had a higher risk of composite adverse maternal and neonatal outcomes.
SPEAKER_02So the labeling effect they speak of here has already been seen a lot in the diabetes literature where patients will be scared to even try a labor. Maybe they've been counseled a little too stringently by their doctors about things like shoulder dystocia and your baby's gonna die. But also when they do labor and during the course of their labor, even if the slightest thing goes wrong, there's one fetal heart rate deceleration that or the labor isn't progressing quite as fast as the doctor would want to, then those kind of things tend to push them towards cesarean more so than the typical patient. The whole team is just sitting around thinking, oh, that baby's too big, it's just not gonna make it down through that pelvis, and really looking for reasons to do a C-section.
SPEAKER_00Yeah. But to establish this labeling effect, you have to do a little bit more. And they did. You have to compare the true positive cases to the false negative cases. So they did this. And compared to true positive cases, false negative cases were associated with a significantly lower rate of induction of labor, intrapartum cesarean delivery, and composite adverse maternal outcomes with no increased risk of adverse neonatal outcomes. That means the truly macrosomic babies who were just not labeled as such did better than the truly normal babies who were incorrectly labeled as macrosomic. So that's evidence of the labeling effect.
SPEAKER_02Yeah, well, that's of course very humbling, because that that really just points to our behavior having a bad effect on the patient. It we can just get so worried about shoulder dissocia that we push things too far in the other direction.
SPEAKER_00Right. And those false positive cases, so these are normal sized babies, had higher rates of operative vaginal delivery, cesarean delivery, and composite adverse maternal outcomes, again, with no difference in the risk of adverse neonatal outcomes.
SPEAKER_02Yeah. So the labeling effect is a real thing, a concrete thing. And the bottom line is that routine ultrasound at 36 weeks to screen for large progestational age fetuses, especially in just the low-risk population, has very poor diagnostic performance and adversely affects patients with this labeling effect. There has been a bit of controversy in OBGYN about whether this kind of ultrasound should be routinely offered. It's not currently recommended that all comers have a late third trimester ultrasound just for growth, but it is a common practice in a lot of obstetric clinics. I've seen that a lot of insurers will add that as part of their routine package. There's the dating ultrasound, anatomy ultrasound, and then a third trimester ultrasound that's paid for. So it's another revenue generating procedure that doesn't necessarily give the patient an upfront$500 ultrasound bill. But in this study, there's a lot of other evidence indicating that it's costing patients in other ways.
SPEAKER_00Yes. Overdiagnosis of macrosomia does not improve neon L outcomes, I think is the point, but significantly increases the rates of cesarean delivery, whereas underdiagnosis doesn't appear to put the baby or mom at enough risk to measure. So I think studies like this affirm why we need really empiric evidence and controlled trials before we routinely add things into clinical practice because they seem to make sense. It sure makes sense that knowing the ultrasound weight or the diabetes or insulin resistant status of a patient will somehow improve outcomes, but you have to prove that in a clinical trial. Now we offer elective cesareans at 5,000 grams for non-diabetics and 4,500 grams for diabetics because that's the threshold that we think makes the most sense right now. And we diagnose gestational diabetes with the two-step test rather than the one-step test because we don't want to overlabel diabetes in a population. And of course, you can talk about whether you use the 130 as a cutoff or 140 as a cutoff and those criteria. But when you do that, you realize this is the conversation about what's the effect of labeling a person as diabetic and does it lead to improve or worse outcomes. And in general, the literature supports diagnosing less gestational diabetes, not more, in this regard. So these are some of the reasons why we make those decisions. And when you read about these, think about this impact. We have to be careful about diagnostic creep where the person who has a 4,400 gram baby or a 4,900 gram baby for the non-diabetic all of a sudden is getting a cesarean without proven benefit.
SPEAKER_02One last thing I'll say on this topic is that liability fears probably play a lot into this as well. Again, with the shoulder dissocia, if there's a bad shoulder dysocia outcome and the baby is large, that lawsuit, of course, is going to be all over that baby's weight. Why didn't you check the weight on a third trimester scan? Why did you allow them to go past whatever 39 weeks when they're measuring so big? Why did you even allow labor at all? And even though none of those are evidence-based arguments, if they could be enough to potentially sway a jury to award some huge number, there was a almost$100 million verdict for an OBGYN outcome, and our policy limits are$1 million per case. So I can see why a lot of OBGYNs would feel safer doing an unnecessary cesarean rather than they just see this and just scares them out of the evidence-based practice.
SPEAKER_00Yeah. And this also just reaffirms that what we're saying and writing about in our literature about MedMal needs to be evidence-based too. And maybe you and I should get into that when we have our next episode in a month. Because I have a couple of examples recently where some comments are being made in popular OBGY and social media that are so far removed that they're actually harmful to us. And so we'll mention that next time and talk about that.
Removing sFlt1 To Buy Time
SPEAKER_02Yeah. Okay, well, let's move along. Did you see this new paper in Nature Medicine that reported on a study where they removed SFLT1 from the blood of preeclamptic women in an effort to prolong their pregnancies?
SPEAKER_00I did. In fact, I had the opportunity to discuss this with David Nelson at the annual clinical and scientific meeting. It certainly is very preliminary and they only have a historic control group, but it's very interesting for sure. So they developed a protein that binds to SFLT1 or SFLIT, as the boys say, and then they used extracorporeal aphoresis, which is just a fancy dialysis to remove the protein from the patient's blood.
SPEAKER_02We have talked about this protein before in in some other studies where they tested for it. I don't think we still have a widely available test for it, at least in my practice, but it is a biomarker that's being explored as a test for preeclampsia, but it's clearly not just a marker. Clearly, it's also related to the actual damage of preeclampsia, too. So the idea is that removing it may slow down the worsening effects of the disease.
SPEAKER_00Yeah. So in this study, they did this in 16 women, and they said that the women stayed pregnant on average about 10 days after treatment, which they estimated was about double the time that they would have stayed pregnant compared to a historic cohort. So they gained five days if we're to believe that comparison. Now, obviously, you need a randomized controlled trial with a contemporary control group and a lot more data before we understand all the ultimate value of all this, but it's exciting in a field where we've not really made any significant progress in decades.
SPEAKER_02Five days could be really important, especially for a very early preterm or even periviable pregnancy. It could get them from 23 to 24 weeks, for example, and maybe a little bit less meaningful if we're talking 30, 32 plus or even 36 plus.
SPEAKER_00Right. I think this is just the beginning and it's a proof of a concept. I suspect we may end up with a drug that just binds to SFLT1 and perhaps other proteins that are associated with preeclampsia and then inactivates them or sequesters them so that they become inactivated. We're going to see lots of therapies like this, I think, in the future for lots of diseases. And the rate of drug development and the type of novel therapies that are going to come out of our ability to now rapidly understand protein structure and develop proteins is changing how we develop drugs and how quickly we develop drugs. So again, that's we're going to talk about that a little bit in the next episode of the podcast, so stay tuned for that. Can I talk about an older paper that I just happened to come across while doing some research?
SPEAKER_02Sure. I guess you're not limited to just April, 2026.
SPEAKER_00Okay, well, this is from April, but 2021 in the Gray Journal. It's entitled Effective Length of Surgery on the Incidence of Venous Thromboembolism after benign hysterectomy. So the authors looked at over 70,000 patients from a standard surgical outcomes database and specifically wanted to see what the effect was of length of surgery on the risk of developing deep main thrombosis after hysterectomy, and they found an increasing risk of venous thromboembolism for every additional 60 minutes of surgery. So every 60 minutes was associated with a 35% increased risk of clot within 30 days of surgery. And the effects were cumulative, so that risk just kept going up. Of course, they also found that abdominal hysterectomy was independently associated with an increased risk compared to minimally invasive hysterectomy. And of course, vagal hysterectomy had the lowest risk overall compared to laparoscopic hysterectomy, and abdominal was the worst.
SPEAKER_02Yeah, so the risks are still overall relatively low. The authors also talk a lot about mechanical alone versus mechanical plus chemo prophylaxis for prevention. So SCDs alone or SCDs plus heparin or low-vinox. The overall rate of all the different types of hysterectomies was 0.4%. But breaking that down for vaginal hysterectomy, it was 0.18%, laparoscopic, 0.3%, and then abdominal hysterectomy, VTE rate was 0.65%.
SPEAKER_00And of course, this is a database, so some of that risk is going to be accounted to other factors. But still, vaginal hysterectomy is faster than other routes when controlling for all patient factors and the effect of lower DVT rate persisted after controlling for the variables they could control for.
Laboring Down Claims Versus RCT Reality
SPEAKER_02All right. Well, we know you're all about vaginal hysterectomies. So let's keep moving along. There was a study out of France in the May 2026 grade journal that's getting some buzz. This was a retrospective study of over 10,000 women in France looking at length of pushing after course of laboring down versus immediate pushing. So the highlighted claim is that nulliparous women pushed only on average 14 minutes and multiparous women only for six minutes, but they had labored down for up to three hours.
SPEAKER_00Yeah, well, and they excluded women who ultimately needed operative vaginal deliveries. And the majority of patients in this study were multiparous. And more importantly, though, I've seen this all over social media too. There was no control group to compare those links of pushing or the outcomes that they report to labor down versus not labor-down group. So any conclusions drawn from it or claims being made from it are essentially baseless. They're just kind of reporting what happened in their hospital.
SPEAKER_02Yeah. Yeah, it's like a just a big case series. So they admit they might not have very accurate recording of how long the patients pushed for. The trick here is they redefined the second stage into passive and active. The average passive part of the second stage was over an hour. And then they added the pushing part to that to get total second stage durations closer to an hour and a half or more. And this was in a population of women mostly multiparous. For many patients, this effectively would have tripled the length of the second stage had they started pushing immediately, which, as you said, they didn't use. Even have a control group that did that. And we already know that the longer the second stage is, the higher the rate of neonatal morbidities. And since they don't have a comparative group, they can't make any claims about safety or any other outcomes on the newborns.
SPEAKER_00In many studies, multiparous patients only push about 14 or 15 minutes anyway. So it could be the case that you're adding an hour to save eight or nine minutes of active pushing. However, we finally have had a high-quality randomized controlled trial that answered the question about delayed pushing. And that's why we have this policy in America. They're comparing what the French do to what the Americans do, and the Americans don't labor down, the French do, is their point. But we had a high-quality paper come out in 2018 in JAMA. And in that study, 2,404 noliparous women with epidurals were randomized to immediate compared with delayed pushing. So this should be the group of people who would most benefit, right? They're first-time moms and they have a dense epidural or whatever. So if you're going to see any benefit, it would be here. The study found that delayed pushing was associated with a longer second stage of labor, of course, but there was no impact on the rate of spontaneous vaginal delivery. However, there was in the laboring down group an increased risk of postpartum hemorrhage, choriaminitis, neonatal acidemia, and evaluations for sepsis with the delayed pushing group. So we stopped doing it.
SPEAKER_02Yeah, that that was by Alison Cahill and colleagues. They found a difference in pushing time of only nine minutes. And that seems to be what a lot of these studies find, where the pushing itself is well, there was a one study we talked about before where people still pushed for longer after delayed or after laboring down. But it's never like you're saving an hour of pushing or anything. It's in the single digits.
SPEAKER_00Right. And that's one of the issues too about them excluding the patients who ultimately had operative vaginal deliveries, because we just took away all the women who did push for two or three hours and then had vacuums or forceps. We took those out of the denominator. And but on social media, this study is being pushed around as if you disallow physiologic birth, although I think 90% of their patients had epidurals, if you disallowed physiologic birth, women would only have to push for four or five minutes. And it gets into a lot of the tropes that you see on social media. But again, there's no comparative data, and they can't claim that it's safe. Our best evidence says that this results in more infections, more hemorrhage, and more enneatal acidemia.
SPEAKER_02Yeah. So for all those risks, saving the nine minutes of pushing is really not worthwhile when you're still not increasing the rate of vaginal delivery by laboring down.
SPEAKER_00Right. So they're essentially just showing off without a comparison group. It would be like me publishing my last five years worth of deliveries or something and talking about how long women push with no comparison group. I will note, though, that most of their patients were in the dorsal authomy position at the time of delivery. And I say that because a lot of times these papers are picked up by, again, natural birth advocates and as if they found some secret. And yeah, like 90% of them had epidurals and they were 98% were on their back when they pushed the babies out. And that certainly doesn't comport elsewhere with what social media talks about a lot. They also practice this very aggressive form of pushing. That's how they define it, that's their word, that's not routinely used in the United States. I think it's what I do in my own practice, but it's certainly not universal here. And that probably affected their length of pushing too. And it's just another thing that a lot of the natural birth advocates probably aren't doing. So the folks who are resharing this study on social media are not saying, yeah, and 90% of women should get an epidural and 98% should be on their back and they should push super aggressively while they're pushing, closed glottis, full out, three 10-second contraction or pushing episodes per contraction. No breaks.
Counseling Fatigue Without Ignoring Risk
SPEAKER_02Yeah, and so those different pushing techniques also were the subject of a randomized trial that found the intense pushing group in nulliprus women saved about 10 minutes compared to the moderate pushing group. So that difference was 28 versus 38 minutes on average. So by moderate pushing, what one definition here, at least in this trial, is patients would only push twice during a contraction and frequently we're allowed to just take a whole contraction off, not push, just relax through it. But the intense pushing has been favored in France because historically the length of the second stage was an absolute indication for cesarean for them. And so the idea of more intense pushing and also strongly distinguishing passive versus active parts of second stage has been favored because that was their way of lowering cesarean delivery. If they got to a certain point just on the time clock of pushing, they would have to do a C-section by their own guidelines they had made up. So this was their kind of way around it. So you can see why laboring down seems very beneficial to them because it doesn't count against that time limit when they define it in that way. And it does shorten the duration of that very intense pushing. So the question has always been whether or not this is associated with increased risks of adverse outcomes. And we have to go with the randomized controlled trial for the answer to that. This newer retrospective study from France really is not groundbreaking at all. But because it does seem to favor laboring down, it's just getting some attention. And I see it a lot. I get it. Why do people want to labor down? It can be a tough sell to skip laboring down, I think. In most cases, it's not like the patient is begging to push and it's the provider saying, no, no, you must labor down because I really want to spend nine minutes less in your room. It's not that the patients often can be tired. Maybe they've they've had trouble with their epidural, they've been in a lot of pain, and now they've just gotten topped up, they're begging to sleep and rest up before they start pushing, they don't have an urge. So then if it seems like the mom's not on board with the immediate pushing, the team's not on board with it, it's not going to be very effective or a good experience. And then, of course, if you add the typical thing we're seeing these days, like the unit is busy and short staffed, there's another delivery or two happening and another emergency happening at the same time, nursing shift change is about to happen, then it's easy to say, just let her take her nap, let her let us get a new fresh team taking over. And then easily one or two hours goes by before anyone even thinks about starting pushing. So this study also addressed some other common concerns. And I'm talking about the 2018 one by Kay Hill.
SPEAKER_00Allison Kay Hill, yeah.
SPEAKER_02So they addressed high fetal station and OP presentation. So if someone is 10 centimeters and zero station and they're OP, then it's gonna be more common for the team to want to labor down and do their position changes and just give time for the baby to descend and rotate, maybe even maybe even try a manual rotation, because they're gonna picture hours and hours and hours of pushing if they start now versus when they're at plus two station and OA. So that I think is the logic. Well, Cahill and their and her colleagues did record if patients were less than or greater than plus two station at the start of pushing, immediate versus delayed, and also their different presentations, occiput posterior versus transverse versus anterior. And at least for the outcome of rate of spontaneous vaginal delivery, there were no differences between any of those groups. They didn't put a breakdown of pushing duration with those groups specifically or overall second stage duration. So that'd be interesting to know. But obviously, I would assume that the total second stage duration would have been a lot higher for the ones that labored down. And again, very likely that the rates of complications like hemorrhages and infections were definitely not better with the delayed pushing in these groups specifically, but these are the ones that people really want to labor down with. So, so all of this I think would be helpful to incorporate when counseling patients, especially if they've seen stuff on TikTok about how in France they labor down and that laboring down is really good, they should know that it that laboring down can increase their rate of complications too. And so if they're counseled in that way and then they say, okay, I get it, but I still really want to nap, I'm so exhausted, then it's not like I would force immediate pushing. But I think it should always be offered and really presented as the preferred option whenever feasible. And I don't think it necessarily is.
Third Stage Myths And Hemorrhage Prevention
SPEAKER_00Yeah. And it's very cultural. In some units, laboring down almost never happens. In other units, it happens almost always for many of the reasons why you discussed, but also just a belief among culturally among the nursing staff that it has some huge benefit. That huge benefit in their mind is saving 50 minutes of pushing or just some tremendous amount, not eight or nine minutes. And they don't really think of it as harmful, particularly if the tracing's okay. They don't they're not worried about they're not worried about that. So that's the importance again of of having controlled data. But I am aware of units that already support the practice of laboring down routinely, is again looking at this French paper just like social media has done and jumping on the bandwagon of this is proof positive of how wonderful this is. Particularly if the last time you push with a patient, you pushed for an hour and a half, and then you read that, oh gosh, they only pushed for 14 minutes, then clearly but of course that's anecdote, not evidence. So there's another study that I have seen on the social media rounds, but this one's an older one.
SPEAKER_02Aaron Ross Powell Another older study? You need to try to keep up with the times.
SPEAKER_00Well, I I am keeping up with the social media times. I found this one on Instagram, but yeah, it's from Midwifery, the journal, in 2013, and it's called Outcomes of Physiologic and Active Third Stage Labor Care Among Women in New Zealand. So this paper claims to show that expectant management of the third stage of labor is superior to active management. It claims that active management was associated with more blood loss, and therefore women should have physiologic management of the third stage of labor.
SPEAKER_02Which is?
SPEAKER_00Which is do nothing. Physiologic management means do nothing. No prophylactic uterotonics, don't touch the placenta, let it sit there for an hour if it wants to. Hands off.
SPEAKER_02Okay. Well, we know that prophylactic uterotonics, which usually is oxytocin, at least in the US, prevents postpartum hemorrhage. And in fact, active management of the third stage of labor is one of the most life-saving things we still do. So what exactly did they find in this study to say otherwise?
SPEAKER_00Well, it's just junk science. Our literature is full of this sort of stuff, and it just amazes me that editors accept these things for publication. But they did a retrospective comparison of estimated blood loss from an uncontrolled group of records maintained by the New Zealand College of Midwives database, and they tried to make a comparison, not realizing, of course, that in a culture where patients are getting uterotonics only sparingly, it's probably being given to those patients who are already bleeding or who have some higher risk of bleeding to begin with. So it's it's not an apples to apples comparison.
SPEAKER_02Right. It's like saying that people who received the first rounds of the COVID vaccine suffered higher mortality compared to those that didn't get it, not accounting for the fact that higher risk patients preferentially were given the vaccines first, that they were already at more risk for complications and the vaccine probably lowered what it would have otherwise been for them. So yeah, a lot that definitely apples to oranges.
SPEAKER_00Yeah, we know this with a high degree of certainty, but I am seeing patients refuse all placenta management and care again at a higher and higher rate because of stuff like this on social media. But this is why we need randomized controlled trials to make everences like this. And we have them. We have plenty of them on this. The 1998 Bristol trial showed a 5.9% rate of hemorrhage in the actively managed patients compared to a 17.9% rate in other patients. Then the 1992 Hitchingbrook trial showed a lower risk and less need for blood transfusions, even among low-risk patients, not just in a group of higher risk patients. And there are tons of similar studies that have been done in different countries, in different parts of the world. And it's clear that on the continent of Africa, hundreds of women die every week of childbirth related to hemorrhage who would not die if they had active management of the third stage of labor. And even in this country where so many women will forego it or have home births where there's no active management, we still have a relatively low mortality rate because we, as soon as they do start bleeding, we call in the calvary or we take them to a hospital and we have blood banks and we can convince them to take the uterotonic once they've started bleeding. It was hard to convince people sometimes for some reason that an ounce of prevention is worth a pound of cure, but these studies show this very explicitly. And it's almost shameful, the paper that we're talking about in Midwifery in 2013, it's almost shameful that people would publish things like this that directly lead to harm of patients.
SPEAKER_02Yeah, we really have to be thoughtful and vigilant about what constitutes good evidence when we're reading through studies and making decisions based on them or conclusions based on them. We really can't trust that just because something is in a journal, and certainly not in a news blast article or social media that that it's a good study, that they're not going to be the ones to weed out the bad studies. We have to weed them out for ourselves.
SPEAKER_00Yeah. Well, and stay tuned for the next episode because our guest hosts and I are going to talk exactly about some of the ideas about what constitutes good evidence. I will also say a lot of times I see stuff on social media and somebody will say a study says this, and it strikes me as like, really, I've never heard that. And then I actually follow the link and it doesn't say that at all. So it's amazing. I don't know that people are just lying, but what percentage of people see something like that and actually click through and read the paper, which is often unrelated or or has just a completely misinterpreted claim that they put out there as proof positive. You see that a lot with people taking lab-based or animal studies and applying it to human physiology and drawing vast conclusions from it. So be careful out there.
SPEAKER_02But well, I look forward to that episode.
SPEAKER_00Yeah. And happy Mother's Day. We're recording this on Mother's Day for the listeners.
SPEAKER_02Yeah, happy Mother's Day to all the moms out there.
SPEAKER_00All right, we'll see you in a couple of weeks.
SPEAKER_01Thanks for listening. Be sure to check out thinking about obgyn.com for more information, and be sure to follow us on Instagram. We'll be back in two weeks.