Ep 174: What to Do If You Might Have a Big Baby

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Today we’re talking about what happens if there is a suspicion that your baby is big. I originally did an episode about this back in 2019 but since then I’ve had so many people reach out and ask about this subject that I thought I should revisit it and update it.

I think it’s coming up more often because more doctors seem to be doing routine third trimester ultrasounds which actually aren’t necessary. These ultrasounds aren’t great at identifying whether or not your baby will be large and can lead to unnecessary interventions down the road. In this episode, we’ll get into the indicators you actually want to pay attention to and the outcomes and treatments you should be aware of for a suspected big baby.

In this Episode, You’ll Learn About:

  • How much does a baby have to weigh in order to be considered “big,” or having macrosomia
  • What factors can increase the risk of having a big baby
  • How macrosomia is diagnosed
  • How accurate (and necessary) ultrasonic screening is in identifying baby size
  • Who should be getting screened
  • What kinds of complications can be caused by having a larger baby
  • How you can help yourself with some prevention strategies and management options

Links Mentioned in the Episode

Keywords

big baby, diabetes, gestational diabetes, large, macrosomia, weight

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Keywords

big baby, diabetes, gestational diabetes, large, macrosomia, weight

Categories

Podcast

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Dr. Nicole (00:00): What is supposed to happen when there is a suspicion that your baby is big? You're definitely going to want to listen to this episode, because what happens in a practice is unfortunately not always in line with the recommended guidelines. This episode is being supported by Bamboobies. Welcome to the All About Pregnancy & Birth podcast. I'm Dr. Nicole Calloway Rankins, a board certified OB GYN who's been in practice for nearly 15 years. I've had the privilege of helping over 1000 babies into this world, and I'm here to help you be calm, confident, and empowered to have a beautiful pregnancy and birth. Quick note, this podcast is for educational purposes only and is not a substitute for medical advice. Check out the full disclaimer at drnicolerankins.com/disclaimer. Now let's get to it.

Dr. Nicole (01:02): Well, hello. Hello. Welcome to another episode of the podcast. This is episode number 174. Thank you for being here with me today in today's episode, you're going to learn what happens if there is a suspicion that your baby is big. Now, I originally talked about this back in 2019, but since that time, some newer evidence has come out about strategies to prevent a big baby. So I'm gonna talk about that. And I've also had so many people reach out to me asking or sharing their stories about what to do in this situation. And I think that's happening more because it seems to be that more doctors are doing kind of routine third trimester ultrasound. A lot of which is not really indicated. And what happens is you end up going down this path of a suspected big baby. When the ultrasound shows that, even though the ultrasound wasn't necessarily indicated. So we're gonna talk about all of those things today. You're gonna learn what the definition is for a suspected big baby or macrosomia is the clinical term. Also some risk factors for having a big baby. What are the risk if your baby is big, what are the risk to you? What are the risk to your baby? And we'll also talk about the management options, including in screening strategies, prevention strategies, um, recommendations for labor and birth.

Dr. Nicole (02:33): All right. So before we get into the episode, let me do a listener shout out. This is from Morgan and the review, says five stars best, and most reassuring, informative podcast. I love it short, sweet, and to the point. And so, so kind, I so appreciate you taking the time to leave that lovely review. And yes, that is the goal here to be reassuring, to be informative. And that is what you are going to get in this episode today. Now also a quick word about this episode supporter Bamboobies. Bamboobies was created by a real life mom who was frustrated at the lack of reusable and comfortable nursing pads. And what Bamboobies does is it combines a smart design with baby and mom friendly materials to provide worry free, effective products that support and empower every mom at every stage of her motherhood journey.

Dr. Nicole (03:27): They have these great washable nursing pads. They provide leak protection all day with a super soft seamless design and leakproof liner. It's the number one sustainable washable nursing pad is designed with a super soft velour that's made from a renewable bamboo. So great for the environment, the heart shape pads cup your breast to be less visible under clothing, no matter your cup size and the round pads allow for more surface area protection for those heavier leaks like for overnight. Its very soft and comfortable on sensitive skin. So head to bamboobies.com. That's B A M B O O B I E S.com. Use the code all about A L L A B O U T to get 40% all full price items. This code is valid through October 23rd. Again, that's bamboobies.com. Use the code all about to get 40% off full price items. All right.

Dr. Nicole (04:26): So let's talk about what to do when there is a suspicion that your baby's big. So first off let's review some terminology. There are two terms that are used for babies that have excessive growth. One is macrosomia. Macrosomia is when there is growth beyond a specific birth weight, regardless of the gestational age. And that is usually defined as 4,500 grams, which is nine pounds, 14 ounces, or 4,000 grams, which is eight pounds, 13 ounces. That definition varies definitely 4,500 is considered for most to be macrosomia, but it, it can vary a bit. And the reason we use grams and actually we use grams, um, in general, in terms of birth weight, is because it's a more uniform definition worldwide. The United States is the only place that uses the backwards nonsensical system of pounds and ounces. Whereas grams makes a lot more logical sense. Its a base 10 system.

Dr. Nicole (05:30): You can hear my math nerdy background coming out. So in the episode you're gonna hear me use grams and not pounds and ounces, but just so you have a rough idea, 4,500 grams is nine pounds, 14 ounces. And I'm gonna say 4,500 grams a lot also 5,000, which is about 11 pounds. Okay. So back to the definitions for babies with, with big growth macrosomia again is a birth weight beyond 4,500 grams or 4,000 grams. A large for gestational age baby is when the birth weight is greater than the 90th percentile for a specific gestational age. So for example, at 37 weeks, the 90th percentile is 3,612 grams. So a baby at 37 weeks who weighed more than 3612 grams would be considered large for gestational age. Okay. 38 weeks. It's bigger. 39 weeks is a little bigger. So you can see the difference in the two. Macrosomia is an absolute bigger than 4,000 or 4,500 grams, large for gestational age means that the baby is bigger based on its specific gestational age.

Dr. Nicole (06:45): Now the risk for issues for both mom and baby go up after 4,000 grams, but it really goes up after 4,500 grams. And it definitely goes up after 5,000 grams, 5,000 grams is again 11 pounds and after 5,000 grams actually after 4,500, but for sure after 5,000, there's an increased risk of cesarean birth, of low Apgar scores, birth injuries, assisted ventilation, increased risk infant mortality. And I'll talk about those in a little bit more detail, but definitely the risk go up after 5,000 and for sure after 4,500, okay. Now let's look at how frequent does this occur. When we look at data from the National Center for Health Statistics, that's through, through the Centers for Disease Control and prevention, about 7.8% of all live born newborns in the United States weigh more than 4,000 grams. So it's not very common. And then when we go higher, only 1% weigh more than 4,500 grams and only 0.1% weigh more than 5,000 grams.

Dr. Nicole (07:59): And that number has actually decreased over time. Okay. It's actually decreased over time. So overall the incidence of big babies is not very common. Now that was with macrosomia. When we look at large for gestational age babies, there's definitely a difference when we look at women who have gestational diabetes or who have obesity, they have higher rates of large for gestational age newborns. In one study that looked at about 10,000 women, the rate of LGA newborns without gestational diabetes, that was about 7.7% in normal weight women, but 12.7% in obese women. So they had bigger babies based on their specific gestational age and in diabetes. The difference is even more in women who have gestational diabetes and a normal weight pregnant person. The rate of large for gestational age baby was 13.6% compared with 22.3% for obese women. So as you can see, risk factors for having a big baby are, if you have maternal pre-pregnancy obesity, that is a big risk factor.

Dr. Nicole (09:14): Also gestational diabetes is a risk factor specifically if it's uncontrolled. Also preexisting maternal diabetes. So diabetes before pregnancy is a risk factor for having a big baby. Additional risk factors for having a big baby are if you have excessive pregnancy weight gain. And I have an episode on weight gain in pregnancy, I can't remember the number off the top of my head, but if you, if you search Dr. Nicole Rankins and weight gain, you'll find it. And I'll also link it in the show notes. Also, if you have a lot of weight gain in between pregnancies, that increases the risk for a big baby, if you have a post term pregnancies, so that's gonna be more than 42 weeks. That's actually very rare that we have pregnancies that go that far, but in general, the bigger, the farther along you go in pregnancy, the bigger the baby's gonna be, that makes sense, cuz the baby's gonna have more time to grow.

Dr. Nicole (10:04): And then probably the biggest risk factor for having a big baby is if you had a prior big baby, you know, if you had a big baby before, you're more likely to have a big baby. Again, some other not as strong risk factors are advanced maternal age. So that is if you are 35 or older at the time of birth, male infant, um, Hispanic or African American ethnicity, if mom herself weighed over 4,000 grams can increase the risk. And again, that makes sense. Sometimes big babies can run in families. There's not an association with dad so much. It's more so with mom. And then there are some rare genetic genetic syndromes that are associated with the big baby. And also again, how far along you are, is going to influence your birth weight. Uh, in 2014, the risk of a birth weight more than 4,500 grams increased from 1.3% at 39 weeks to between 39 weeks to 40 weeks to 2.9% when the gestational age is beyond 41 weeks.

Dr. Nicole (11:08): So the longer you stay pregnant, the bigger the baby's gonna get, that just makes sense. And that'll come into play. Um, when I talk about whether or not induction is recommended for a suspected big baby, it's also important to know that these risk factors are synergistic, meaning that if you have multiple risk factors, it's going to increase your risk of having a macrosomic baby. So especially if you have gestational diabetes, if you have obesity, if you have excessive weight gain during pregnancy, um, those three things together, especially although they're independently associated with macrosomia together, they will increase the risk even more than if, if you just added them up individually. So things can be synergistic. You have more than risk, more than one risk factor it can increase the chances of having a big baby even more. So let's move on and talk about how we diagnose macrosomia.

Dr. Nicole (12:08): Well, really the accurate diagnosis can only be made after a baby is born and when we can actually weigh the baby, the prenatal prediction of newborn weight is actually very, very, very imprecise. There are formulas that are used with ultrasound. You do some measurements, it uses a formula to try to estimate the weight, but they can have errors, um, as high as 20%, sometimes even higher. When we look at the ability for ultrasound to predict whether or not a baby is big, it's actually pretty poor. There's a sensitivity of 56% and a specificity of 92% for predicting birth weight more than 4,000 grams. And what does that mean? So sensitivity means a 56% means that if someone actually has a big baby, that the ultrasound will show it, um, it ju it just doesn't do it very well. And what specificity of 92% means is that it's actually pretty good at predicting that a baby is not big.

Dr. Nicole (13:13): So if you get a ultrasound late in the third trimester and it says that the weight is normal or not suspected to be big, then that is most likely accurate. However, if it suspects that your baby is big, it's actually not very accurate. And that decreases that accuracy decreases the bigger the baby actually is. One study showed that, uh, ultrasound was only able to accurately predict birth weight more than 4,500 grams in 33 to 44% of cases. So in less than half of cases, was it actually able to predict whether or not the baby was going to be big. Now studies have actually shown that there are some other things that can predict just as well, if not better than ultrasound. Interestingly, women who have had babies before can do a pretty good job of predicting their baby's weight as well as ultrasound, or even as well as physical exam.

Dr. Nicole (14:13): So literally just asking the pregnant person, does this baby feel bigger than your last baby? Does this baby feel big to you? Does this baby--how does this baby compare in size to your last baby, can be just as good at predicting a baby's weight compared to ultrasound or physical exam. And speaking a physical exam, uh, ultrasound has also not been shown to be any more accurate than physical exams. So literally just feeling and see how big we think the baby feels based on something called Leopold's maneuvers, where we just feel and, and, and get an estimate of the baby's weight that is just as good as ultrasound. So I say all that to say that the measurement or estimate of the baby's weight close to term is not very accurate. It's not very good at predicting whether or not the baby is big. And let me back up and say, it's not that it's not very good at predicting weight. It's actually good at predicting, if the baby's gonna be a normal weight, it's just not good at predicting whether or not the baby is going to be big.

Dr. Nicole (15:21): All right. So what are some of the complications or risks or issues that can occur from having a big baby? Because that's the whole reason why we get concerned about a big baby is what are the problems? You know, if there were no issues when a baby is big, then we wouldn't be worried about it, but because there are things that can happen when a baby is big, that's why we get concerned. So let me start off by talking about the risk that can happen for mom. The biggest risk for a big baby is an increased risk of cesarean birth. The risk for Cesarean birth for women who have a baby that is estimated to be more than 4,500 grams. The risk for cesarean birth is at least twice that of women who are not suspected to have a big baby. Also, we see that labor can be slower or, um, stop in with macrosomia or with bigger babies.

Dr. Nicole (16:15): So that's called labor protraction disorders or arrest disorders. Now some of that is due to the fact that we suspect that the baby is big. And then we're like on a higher alert, looking for problems or reasons for doing a C-section. As a matter of fact, studies have shown that the inaccurate ultrasound estimate of weight will predispose a woman to a diagnosis of labor problems or cesarean birth, independent of the actual birth weight. Okay. So what that means is re regardless of the actual birth weight, when we suspect that the baby is big, there tends to be more of a tendency to say that, oh, labor is slow or labor has stopped, or we recommend a C-section and this is going to come into play when I talk about some of the management options, okay. And whether or not ultrasound in the third trimester is routinely recommended.

Dr. Nicole (17:18): Now, some other things that can happen for mom that put mom at an increased risk are, or, or increased risk for mom, there's an increased risk of postpartum hemorrhage. There's an increased risk of chorioamnionitis, which is infection of the membranes in the placenta. There's also an increased risk of significant vaginal tears, third or fourth degree tears. And those are more significant and tears can be graded as first, second, third or fourth. I talk in detail about vaginal tears inside the Birth Preparation Course. Um, that's my online childbirth education class. Uh, if you're interested, you can check out the class at drnicolerankins.com/enroll, but significant vaginal tears, like third or fourth degree, which go through more muscle and fourth through the rectum, you have an increased risk. And that makes sense, right? Because you have a bigger baby that's coming through the vagina.

Dr. Nicole (18:04): You have more of an opportunity to cause some damage on the way out. Okay. So what are the potential complications or risk for the baby? The most serious complication is shoulder dystocia and shoulder dystocia is when a baby's shoulder gets trapped under the pubic bone on the way out. So what happens is the head delivers and then the rest of the body doesn't come out because the shoulder is stuck. It's stuck under the pubic bone. And the pubic bone is at hard firm bone, right in front of your, you can feel it. Um, I'm literally sitting here. Y'all like touching my own pubic bone as if you can see me, but the pubic bone is like the pubic bone and the shoulder literally gets stuck. And the reason that that is a problem is be for a couple reasons, um, one, it can cut off the oxygen supply to the baby, but there are other things that can occur as well.

Dr. Nicole (19:00): So there's a possibility of injuring what's called the brachial plexus. The brachial plexus is the network of nerves that sends signals from your spinal cord through your shoulder, arm and hand. And there's a possibility that those nerves cuz they, they run like in the neck can get stretched during the course of a shoulder dystocia. And if they are stretched to the point of injury, then that can be problematic. It can make it so that arm is not functional or the wrist is not functional or the hand is not functional on that side of the shoulder dystocia. There's also a possibility of breaking the collarbone or the clavicle in an effort to get the baby delivered or the humorous, which is the long bone in the arm. Um, those definitely both sound scary. Fortunately they typically resolve with no long term problems and they're both pretty rare.

Dr. Nicole (19:56): And then as in, as I said, in rare cases, shoulder dystocia can result from, can result in a lack of oxygen, which can then lead to brain damage or death. Those are catastrophic circumstances when a shoulder dystocia happens. Um, and very rare that that that happens. But, um, I do have to tell you, you know, the reality of that possibility also shoulder dystocia can be associated with the increased risk of postpartum hemorrhage also associated with more severe perineal lacerations for mom and some of the maneuvers that are used to help free the shoulder dystocia can sometime, sometimes cause uh, nerve injury in the mom's legs. And in very rare cases, separation of the pubic bone, these are very rare things that I have have not ever seen in my career, knock on wood hope to never see, but they, they are possible. So how often does shoulder dystocia occur?

Dr. Nicole (20:52): Well shoulder dystocia occurs in up to 3% of all vaginal births and the risk increases to up to 14% when the birth weight is more than 4,500 grams when there is maternal diabetes present, whether that's gestational or preexisting with a birth weight of 4,500 grams or more, the rate of shoulder dystocia is on the low end 20% and can be as high as 50%. So why is shoulder dystocia more likely in the presence of diabetes? Well, what happens is that babies who are big because of maternal glucose intolerance. So because of mom's blood sugar, not being in good control, they tend to have more total body fat and they tend to have larger shoulder and upper extremities circumference. So that area, the shoulder area tends to be larger. They have tend to have more, um, skin actually and fat up on the upper extremities. So that is going to make it more likely that the shoulders are going to get stuck.

Dr. Nicole (22:00): So that's why we believe shoulder dystocia is higher in moms that have diabetes. Now it is important to note that although macrosomia most certainly increases the risk for shoulder dystocia, most instances of shoulder dystocia actually happen in babies that are of normal birth weight. And it's actually an unpredictable thing that can happen with any birth. Okay. So yes, baby being suspected to be big will increase the risk of shoulder dystocia, but most shoulder dystocias are completely unpredictable events and they happen in newborns of normal birth weight. And also most macrosomic newborns actually don't have a shoulder dystocia. Okay. So the risk is higher, but most don't. All right. Now, some other things that can happen for a baby if, um, in the, uh, for babies that are big, they can have a increased risk of a lower five minute Apgar score. They have increased issues with respiratory problems, um, increased chances of being admitted to the NICU.

Dr. Nicole (23:09): They also, uh, are more likely to have low blood sugar and where that comes from is that what hap and that's particularly in the case of moms with diabetes. So what happens is if mom's blood sugar is high, if your blood sugar is poorly controlled and stays on the high side, when you have gestational diabetes, or if you have diabetes before pregnancy glucose crosses the placenta, all right, so that sugar will cross the placenta, get into your baby's bloodstream. And what happens is your baby then produces extra insulin in order to lower its blood sugar. That insulin will also lower mom's blood sugar, but really it's the glucose crossing the placenta, getting to the baby. And then the baby has to make extra insulin. And then after the baby's born and they're cut off from that high blood sugar from mom, then they still have all this extra circulating ES uh, insulin around.

Dr. Nicole (24:15): And then that is going to lead to the blood sugar going down. So insulin is the, what decreases our blood sugar in our bodies. When you have diabetes, you don't make enough of your own insulin. So again, if mom's blood sugar is high, it can lead to low blood sugar because the baby is compensating for mom's high blood sugar. And then when they're cut off from that high blood sugar, it puts them at risk for low blood sugar. Okay. And then the final thing is that actually babies that are big at birth, they actually have an increased risk of being overweight or obese later in life compared to babies that are not macrosomic, all right. So we have a lot of reasons to want to try and prevent babies from being big. So let's talk about what prevention strategies are there and then we'll talk about management.

Dr. Nicole (25:07): So unfortunately, actually first lemme talk about screening. Okay. So there are no guidelines that recommend screening for macrosomia in just general OB populations. So if you're going along, you're otherwise healthy, don't have any issues with your pregnancy, we're not suspecting that the baby is big based on fundal height. Fundal height isn't a great measurement of suspecting or assessing whether or not a baby is big, but it's not a bad rough estimate either. But if you're going along no issues, then you do not need routine ultrasound at the end of pregnancy, really, for any reason, um, it, it, for any reason, uh, it just doesn't need to be done. And it increases the chances of finding issues that aren't really a problem and it doesn't improve outcomes, especially in relation to big baby. So there's no recommendation that if you're going along, things look good that you need an ultrasound like routinely just to look at fetal weight.

Dr. Nicole (26:10): If there's not a suspicion based on clinical exam that the baby is actually big. Now in select populations, yes, it may be good to get a third trimester ultrasound to look at the weight, even though we know it could be inaccurate, but in select populations, maybe it may help us make some decisions. So if you have diabetes, then it may help us. Especially if your blood sugar is poorly controlled because if your blood sugar is poorly controlled, we know that that greatly increases the risk of the baby being big. If you had a previous big baby and the labor and birth was complicated, then that may be a reason to get an ultrasound. Okay. So if you had a previous big baby, baby came out fine, then you've proven that you can have big babies. There's no reason to get an ultrasound otherwise, unless you really suspect the next baby is huge.

Dr. Nicole (27:00): So if you have a previous big baby and there were problems, then that may be a reason to get an ultrasound. Or if you had a previous shoulder dystocia, maybe that's a reason to get an ultrasound, but even that is weak. So this routine like third trimester ultrasound, just to see what the baby weighs or looks like is really not indicated unless there is a clinical suspicion that the baby is big. All right. So that's for screening. Screening really isn't necessary. So then what about prevention? Really, what has been shown to reduce macrosomia are exercise. Okay. Exercise actually has been shown to help also really controlling blood sugars in women who have diabetes has been shown to help. And if you have a BMI greater than 40 before pregnancy, pre-pregnancy bariatric surgery may actually help reduce the risk of having a big baby. In digging down to that in a little bit further, exercise isn't just good for preventing macrosomia, it also helps with weight gain. So you're not gonna gain as much weight. And one study showed that there was a 20% lower rate of cesarean birth. So exercise can be really important to help with your overall health. And it doesn't have to be anything major, you know, 20 to 30 minutes of moderate exercise is great. Walking is great. Prenatal yoga is great. Um, but exercise, you know, four or five days a week is really gonna be helpful and it sets the stage for good, for good habits, for long term exercise. Pregnancy can be a great time to implement those new, um, habits and things to help you have better health.

Dr. Nicole (28:51): In another study, looking at a meta-analysis of 15 high quality studies that looked at exercise, it found that any type of exercise, any type of exercise found that macrosomia was reduced by 39%. So take this as a sign, a, a gentle nudge to help get your body moving during your pregnancy, because it's really, really going to be beneficial for you. And again, it doesn't have to be anything major. Walking is fine. Swimming is great. Strength training is great to help reduce the risk of macrosomia and your overall health. All right, now probably the two big things that everybody hears about are labor induction and cesarean. So first let me talk about labor induction.

Dr. Nicole (29:43): So the data on whether or not labor induction helps reduce the issues associated with macrosoma is macrosomia is really, really mixed. Um, ACOG is very clear that labor induction definitely should not happen before 39 weeks. Like that part is very clear. It does not reduce the risk of shoulder dystocia before 39 weeks. And, and you think it makes sense, right? If you induce labor, then the baby is going to be smaller. So therefore some of the risk associated, particularly shoulder dystocia are not going to be as high, but the data just does not bear that out. So ACOG does not recommend and counsels or recommends against induction before 39 weeks in order to improve outcomes for moms and babies related to a suspected big baby. However, after 39 weeks, or 39 weeks or later by 39 weeks, I mean 39 weeks and zero days or later, then it's reasonable to offer induction.

Dr. Nicole (30:49): Some studies have shown that may, maybe it may slightly improve outcomes. Some studies have shown that it does not. So ACOG does not say that it is recommended to induce labor after 39 weeks. Um, because there, there are no proven benefits. ACOG does clearly say we do not induce before 39 weeks. I think you will hear a lot of OB GYNs say that the recommendation is to induce after 39 weeks for a suspected big baby. And that just is not true. The data just does not support that ACOG does not support that. Um, ACOG says it's really an individualized decision and I'm gonna read their statement of what they say about, um, kind of a summary statement in just a minute. Okay. So that's for labor induction. Now, what is the recommendation for C-section? So the recommendation for C-section and this is based on expert opinion.

Dr. Nicole (31:49): Okay. So ACOG says, given the absence of randomized clinical trials, planned cesarean birth for suspected macrosomia is controversial and is based on expert opinion. So this isn't necessarily based. It's not necessarily, it's not based on a lot of data. It's more so an expert opinion. So the recommendation is C-section is offered or recommended if the birth weight is suspected to be greater than 5,000 grams or 11 pounds in a nondiabetic mother, 5,000 grams and greater than 4,500 grams in a diabetic mom. So that's nine pounds, 14 ounces. And that difference again, is because babies with diabetes have a different distribution of fat so that their shoulders and extremities are wider. So that there's an increased risk of shoulder dystocia. So that's why that number is there. All right. So 4,500 grams for diabetic, 5,000 grams in a non-diabetic. And you don't have to, um, you don't have to have a C-section, you know, you, you never have to have a C-section, but it certainly is offered and recommended.

Dr. Nicole (33:01): And honestly, I can say that it is not as common that babies are gonna be born vaginally that are greater than 5,000 grams greater than 11 pounds. Um, but so, you know, it's not, not likely that you're gonna have a, a vaginal birth is just sort of a, it is just rare for it to happen. Um, but I, I do wanna also be honest that it's, it's offered recommended based on expert opinion and not necessarily based on data, but I think it's a sound expert opinion. Based on my experience. Now, I also wanna be clear that C-section doesn't reduce or doesn't eliminate the risk of birth trauma for the baby. It does definitely reduce it, but you can actually still have difficulties with baby being delivered at a C-section. I know it may sound crazy, but sometimes they can get stuck. It can be hard for them to get out of the incision without like almost fileting the uterus open.

Dr. Nicole (33:59): So C-section reduces, but does not eliminate the risk of birth trauma for a big baby. Okay. So that's the recommendation for C-section. Now, otherwise, if people aren't attempting a vaginal birth and, um, have a suspected big baby, we tend to be less aggressive with Pitocin. So it tends to be kind of like either labor progresses on its own, or it doesn't, we don't tend to be super aggressive with Pitocin. And this is, or it's good for you to know what the expected course of labor looks like in terms of things to look out for. I talk about that, uh, in detail, in the Birth Preparation Course, again, my online childbirth education class, you can check that out and side note, I recommend childbirth education for everybody to understand what labor is gonna be like. But I think it's really important, especially in the setting of if you have any issues or concerns, we're also less likely to do operative vaginal births, so less likely to do vacuum, less likely to do forceps.

Dr. Nicole (35:04): And essentially that is because we don't wanna pull the head down and then the shoulders get stuck. So we're less likely to do an operative vaginal birth if we suspect that the baby is big. So it really should be an individualized plan in terms of what happens when there's suspicion that a baby's big, if it's a third trimester ultrasound, you otherwise don't have any problems with your pregnancy, you're healthy, you're weight gain has been reasonable. You know, you don't have diabetes. Um, certainly if you wanna try, you wanna try, we had this I've, I've seen both instances where people have had suspected big baby. Actually, I've seen everything. I've seen people that have suspected big baby, and then they decide to go for C-section and the baby is actually a normal size. That's honestly what I've seen the most. I've seen people have suspected big baby.

Dr. Nicole (36:02): They decide to get induced or that they wait to go into labor on their own. And then the baby is quite normal in size. I've seen that happen quite a bit as well. And then there's also suspected big baby. Baby is big, baby delivers vaginally and suspected big baby, try to go into labor, baby doesn't fit, go to C-section and baby is huge. So it really is difficult to predict. What I would say is that you really just wanna be careful about going to look for things. If there are no reason to go look for them. So I know it's tempting to say like, oh yeah, great. I can have another ultrasound, but keep in mind that that ultrasound is gonna come with information. And then what do you do with it? There's no evidence that it's going to, um, going to help. And as a matter of fact, ACOG and their document safe prevention of first cesarean, let me just tell you what they say.

Dr. Nicole (36:55): And I'm I'm reading. This is a direct quote regarding suspected big babies. So suspected fetal macrosomia is not an indication for delivery. And rarely is an indication for cesarean delivery. The prevalence of birth weight of 5,000 grams or more is rare, and patients should be counseled that estimates of fetal weight, particularly late in gestation are imprecise. Even when these thresholds are not reached screening ultrasonography performed latent pregnancy has been associated with the unintended consequence of increased cesarean delivery with no evidence of neonatal benefit, thus ultrasonography for estimated fetal weight in the third trimester should be used sparingly and with clear indications. Okay. So I think that's just a nice summary wrap up of what happens with a big baby. Okay. And before we head into the episode recap, let me just tell you a quick word again about this week's podcast supporter, Bamboobies. Bamboobies puts moms first.

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Dr. Nicole (39:05): Use the code all about A L L A B O U T, and get 40% off full price items. This code is valid through October 23rd. Okay. So just to recap, the episode macrosomia is growth beyond 4,000 or 4,500 grams. Typically we use 4,500 grams. That's nine pounds, 14 ounce ounces. Ultrasound is not good at predicting macrosomia. So really it's not recommended routinely in the third trimester, be careful about getting it. C-section is offered or recommended if the estimated weight is greater than 5,000 grams, that's 11 pounds in a nondiabetic mom, 4,500 grams in a diabetic mom. And that's because diabetic babies or, or babies of diabetic moms tend to have an increase shoulder, um, with an upper extremity fat. Induction before 39 weeks is not recommended for macrosomia after 39 weeks, it is reasonable, but the evidence is mixed as to whether or not an improve out improves outcomes.

Dr. Nicole (40:09): Uh, and the management of macrosomia is really individualized, knowing that your risk is gonna be higher if you have multiple risk factors. So if you're obese, if you have had a lot of weight gain, if you have gestational diabetes, for instance, then your risk is going to be higher than someone who doesn't have those things. So it really is an individualized approached. And again, I will reiterate that routine ultrasound in the third trimester to look for a big baby is not recommended. Okay. All right. And last thing I'll say is if you wanna know more about labor, birth, what to expect, all of those good, great things and do check out the Birth Preparation Course, that is my online childbirth education class that will get you calm, confident, and empowered to have a beautiful birth. We talk about things in there. Like I even talk about shoulder dystocia in more detail as well, do check out all the details of the Birth Preparation Course at drnicolerankins.com/enroll. Nearly 2000 mamas have gone through the course. And I would love to have you too. Okay. So there you have it. Do me a solid share this podcast with a friend, sharing is caring, and it helps me to reach and serve more pregnant folks. Also subscribe to the podcast in Apple Podcast or wherever you're listening to me right now. If you feel so inclined, I would really appreciate you leaving an honest review in Apple Podcast. It helps other women to find the show. And I just love hearing what you have to say about the show. Do come follow me over on the gram. I'm @drnicolerankins there, and I share more information, lots of good, great tips about pregnancy birth and postpartum as well. So that's it for this episode do come on back next week. And until then, remember you deserve a beautiful pregnancy and birth.

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