Episode 307 Dr. Christina Pinnock + High-Risk Situations & What They Mean for TOLAC

57m | Jun 10, 2024

Dr. Christina Pinnock is a Maternal Fetal Medicine Specialist/Perinatologist based in California and creator of the ZerotoFour Podcast. She is here to help us tackle topics like what constitutes a high-risk pregnancy, lupus, preeclampsia, HELLP syndrome, gestational diabetes, fibroids, and bicornuate uteruses and how they relate to VBAC. 

The overarching theme of this episode is that all pregnancies are individual experiences. If you are hoping to achieve a VBAC and you have pregnancy complications, find a provider whose goals align with yours. By ensuring that your comfort levels are a good match, you are on your way to a safe and empowering birth experience!

Dr. Pinnock’s Website and Podcast

Needed Website

How to VBAC: The Ultimate Prep Course for Parents

Full Transcript under Episode Details 

00:58 Review of the Week

03:13 Dr. Christina Pinnock

03:56 Importance of a VBAC-supportive provider

06:36 High-risk pregnancies

11:02 Lupus and TOLAC

14:31 Preeclampsia 

17:19 Varying ranges of preeclampsia

20:46 HELLP Syndrome 

26:36 Other High-risk situations 

27:54 Gestational Diabetes

35:00 Inductions with gestational diabetes

42:25 Fibroids 

46:33 Do fibroids tend to grow during pregnancy? 

51:20 Bicornuate Uterus

Meagan: Have you ever been told that you were high risk, so you’ll be unable to TOLAC? Or maybe you can totally TOLAC assuming nothing high-risk comes into play? What does high risk mean? We often get questions in our inbox asking if having your previous cesarean makes them high risk. Or questions about topics like preeclampsiaclampsia, gestational diabetes, bicornuate uterus, fibroids, and more. 

I am so excited to have board-certified OB/GYN Dr. Christina Pinnock on the show today. She is a high-risk pregnancy doctor passionate about educating women along their pregnancy journeys so they can be more informed and comfortable during their pregnancy. She is located in California and has a podcast of her own called “ZerotoFour” where she talks about topics that will help first-time moms prepare for, thrive, and recover from pregnancy as well as shares evidence-based information and answers everyday questions like we are going to discuss today. 

00:58 Review of the Week

Meagan: We do have a Review of the Week, so I'm going to jump into that and then we can dive in to get into these fantastic questions from Dr. Christina Pinnock. 

Today’s reviewer's name is Obsessed!!!! It says, “The best VBAC and birth podcast. I am grateful to have discovered Meagan and this podcast. I definitely believe listening to stories of these amazing women and their parent’s course helped me achieve my two VBACs. Thank you for all you do The VBAC Link.”

Oh, thank you so much Obsessed!!!!!  And as always if you wouldn’t mind, drop us a review leave us a comment and you never know, it may be read on the next podcast. 

03:13 Dr. Christina Pinnock

Meagan: Okay, Women of Strength. I am seriously so, so excited to have our guest here with us today! Dr. Christina, is it Pinnock? How do you say it?

 Dr. Pinnock: Yes that’s perfect.

Meagan: Ok, just wanted to make sure I was saying it correctly. Welcome to the show! You guys, she is amazing and has been so gracious to accept our invitation here to today to talk about high-risk pregnancy and what it means. Hopefully, we’ll talk a little bit about gestational diabetes because that's a big one when it comes to VBAC. And if we have time, so much more. So welcome to the show and thank you again for being here.

Dr. Pinnock: Thank you so much for having me, I'm excited to be here and chat with you and your audience about these great topics, so thank you.

03:56 Importance of a VBAC-supportive provider

Meagan: Yes! Okay well, this isn’t a question we had talked about, but I’m curious. Being in California, do you find it hard to find support for VBAC or do you find it easy? I mean, California is so big and you’re in Mountain View. So I don’t know exactly where that is. You said the Bay Area, right? So how is it in your area? How is VBAC viewed in the provider world in your area?

Dr. Pinnock: Yeah, that’s a good question. I actually did most of my training on the East Coast, so it’s been a good experience seeing the differences in coastal practices. I think where I did my training we were pretty open to VBACs and supported them. In California, I’ve had a similar experience and I think it really depends on where you are.  I’m in the San Francisco Bay Area and I work at an institution where we support TOLACs and want our moms to VBAC as long as it’s safe and it’s what they desire. But I really think the opportunity to TOLAC depends on your individual OB provider that you have and their comfort in offering that. And importantly, the hospital resources that you have available in your area. 

California’s huge and depending on where you live it can be a very, very different infrastructure both geographically and specifically within the hospital. And so I really think that differences in that offering is based around those resources rather than maybe patient desire or even sometimes provider desire. So it really just depends on those things. 

Meagan: That’s so good to know. I mean, we tell our community all the time that provider is a really, really big key when it comes to being supported. But also I love that you were talking about the actual hospital because for me with my second– I had a VBAC after 2 C-sections and with my second, my provider was 100% gung-ho and super supportive. But in the end, I ended up switching because the hospital was going to end up restricting my provider in supporting me in the way he wanted to support me, right? So it’s also really important to vet your location and your hospital.

Dr. Pinnock: Yes, absolutely. Sometimes, someone may live in a location where they don’t have that choice, unfortunately. If you do have that choice and you can choose hospitals and providers that can support it, by all means if you have that ability. 

06:36 High-risk pregnancies

Meagan: Absolutely. Ok well, let's dive in more to high-risk. So a lot of the time, I'd love to see what you think about this. A lot of the time, providers will tell moms because they’ve had a previous Cesarean, not even a special scar or anything like that, that they are automatically grouped into the high-risk category. 

So I don’t know what your thoughts are on that in general, but let’s talk more about high-risk pregnancy. What does it mean? What does it look like for TOLAC? How is it usually treated? And are there often restrictions given for those moms? 

Dr. Pinnock: Yeah, no. That’s a really good question. One thing about pregnancy, there’s some level of risk in all pregnancies. No matter if you're completely healthy, no medical problems, or you're trying to TOLAC, or you have other medical conditions that exist before pregnancy, all pregnancies carry some level of risk but not all the risks are equal. 

There are some conditions that the mother can have before pregnancy that can put her pregnancy at a higher risk of developing some complications. There are some conditions that can actually develop during pregnancy that can cause the pregnancy to be at a higher risk of developing complications. Lastly, there are some conditions specific to the placenta, the baby, how the baby developed, or even the genetic makeup of the baby that can contribute to a high risk of having complications. All of these three categories can impact the status of your pregnancy being considered high-risk. 

So typically, if you have a condition that falls in one of those three boats, then your pregnancy could be considered a higher risk. Usually having a previous C-section or even two previous C-sections by itself is not really something that I would use to classify someone as having a high-risk pregnancy. I do think that definitely talking with your provider about your desire for delivery earlier on can help both people to be on the same page, but if you otherwise have nothing else going on in the pregnancy and you have one previous C-section or even two previous C-sections, I think the pregnancy itself, I wouldn’t consider it a high-risk pregnancy. 

Meagan: That’s good to know. 

Dr. Pinnock: Yeah no, absolutely. And when you think about the delivery, I think about it a little bit differently than the pregnancy. I think for the delivery if you are interested in having a TOLAC and you have a previous C-Section or two, then the management of your delivery and the risk of your delivery isn’t the same as someone who hasn’t had a C-section. I think about them as like two different boats. 

But overall, conditions that are related to maternal health can be high blood pressure, diabetes, and autoimmune conditions like lupus. Those things can cause your pregnancy to be considered high-risk. A good example of a few things that can develop in pregnancy that can make your pregnancy high-risk include things like preeclampsia which is high blood pressures of pregnancy. Having twins or having triplets can make your pregnancy a higher risk. In some instances, even gestational diabetes depending on what’s going on and where you are can be considered a pregnancy with some high-risk features. 

And then genetic conditions for baby whether that’s a difference in how one of your babies’ organs developed, or a genetic condition that’s discovered from testing; any of those things can really impact that high-risk status and how your pregnancy will be monitored and managed after that. 

Meagan: Ah these are all such great topics and actually things that we get in our inbox. Like, “Hey, I have lupus,” or we’ll have one of our VBAC doulas say, “Hey, I have a client who has lupus. She really wants to TOLAC and have a VBAC. What does that mean for her?” 

Obviously, all of these conditions are going to be treated differently throughout the pregnancy and probably even during the labor and delivery portion. 

11:02 Lupus and TOLAC 

Meagan: I don't know if we can touch on a couple of those like lupus. What does that look like for someone? If I have lupus coming in, I’m doing okay right now. I have it. What does that look like for someone wanting to TOLAC and to have a VBAC?

Dr Pinnock: Yeah. I think it’s similar to your first question about whether a C-section would make your pregnancy considered high-risk. So the lupus diagnosis would increase the risk of certain medical conditions happening in pregnancy relating to both mom and baby. Your doctor may get some extra blood work to monitor how your lupus is progressing in pregnancy. Your doctor may get some extra ultrasounds to make sure that baby isn’t too small and add some extra monitoring to make sure that baby is staying safe and that if there is a risk for baby to be in distress that that is picked up. 

And so the actual monitoring and management of the pregnancy is usually done with the help of a high-risk pregnancy doctor like myself with an OB provider. That is really specific to what is going on with that person. If everything goes smoothly and lupus stays under control and we get to the moment where we’re thinking about how we’re going to deliver baby, that’s sort of a separate boat. In an ideal world, everything goes well in terms of the lupus and pregnancy and if you’re interested in having a TOLAC, having a diagnosis of lupus should not restrict you from that option. You can still have that as an option but it really just depends on the specifics of how your pregnancy has unfolded. 

Have you developed any other conditions like high blood pressures in pregnancy or preeclampsiaclampsia where your doctor is maybe thinking you may need to deliver earlier? Are there things going on with your baby where we think baby is under more stress where we would really need to be very intentional about how we deliver baby? It’s a really nuanced thing and it’s based on the specifics on that person’s condition. I think an overarching theme is whatever is going on with the pregnancy that impacts the delivery if things are not going as smoothly. But if things are going smoothly and you want to try for a TOLAC, that’s not necessarily a reason to say, “No, you absolutely can’t do this,” unless there are specific conditions that came up in your pregnancy that make it less safe for either you or baby as the mom. 

Meagan: Yeah. Something that I’m just hearing you say so much that’s standing out is that really is individual, depending on that individual and depending on that individual’s case. I think that’s something important for listeners to hear because someone who may have lupus that’s going really, really fine, TOLACs going to be a really great option for them. But someone who may have active symptoms and it’s going and it’s really hard, that may be a different suggestion in the end. But I like that you’re like, We’re in this boat and then we travel over to this boat into this time, and then it’s a matter of how we float that boat and how we get to our destination.

Dr. Pinnock: Exactly.

14:31 Preeclampsia 

Meagan: Would you say that the same thing goes for preeclampsia? Preeclampsia can develop at any stage of pregnancy. I mean, we've had clients in weeks 18-20 develop it and then have to be really closely watched and all of these things. Is that someone also where you would say the same thing? Where it’s like, We’re in this boat doing these things and these tests and monitoring, and then again we get into this next boat and we have to decide what the best route is?

Dr. Pinnock: Yeah, no. That’s a good question. I think it’s similar but a little different with preeclampsia. It depends on the type of preeclampsia that’s going on. Preeclampsia is a spectrum and with the part of the spectrum that’s more on the severe side, we still try for a vaginal birth. It really depends on, as you’ve mentioned, how far along you are in the pregnancy.

Maybe you are 28 weeks and you have such a severe form of preeclampsia that your doctor is like, “I don’t think we can get any more time with the pregnancy,” that’s a very different situation than someone who has a very non-severe form of preeclampsia at 39 weeks who wants to TOLAC and have all of those options available. 

It really does depend but the overall theme with preeclampsia if you do want to try for a vaginal birth and your health and baby’s health are stable in the moment, then usually we do try as much as possible to have a vaginal birth. But things like very early gestational age and really severe complications of preeclampsia make the possibility of having a vaginal birth less likely. It makes the possibility of someone who wants to TOLAC in that setting less likely. It really depends on the severity of that spectrum of preeclampsia, but we always try for a vaginal birth if we can. 

Meagan: Yeah. This may be too hard of a question to answer, but can we talk about that range and the severity? What does a low to moderate to severe case of preeclampsia look like in a person? What would be considered that severe, Hey, we might need to reconsider our birth desire here,” to “Hey, you have it. It’s really low right now,” or to “We’re in choppy waters right now.”

17:19 Varying ranges of preeclampsia

Dr. Pinnock: That’s a good question. Pre-e is defined as elevated blood pressure in pregnancy after 20 weeks. So once you hit 20 weeks, if your blood pressures are elevated, 140/90 times multiple times and we see any evidence of preeclampsia’s impact in some organs in your body.

One of the most common things that we used to use to diagnose is the presence of protein in the urine. Once we see that, we’re like, “Oh, man. I think you may have preeclampsia,” then we do an evaluation of the rest of the body to understand how severe it is. Preeclampsia is a disease that’s thought to develop from the placenta when it implanted. It can cause dysfunction or impact on the organs. It can cause severe headaches. It can cause changes in your vision and problems with your blood cells, your liver, your lungs, and your kidneys. 

We go from head to toe and take a look at how those organs are being impacted by preeclampsia and then we ask you how you’re doing. If you’re having a headache, if you’re having changes in your vision, pain in the belly, and all of that, it helps us to understand the severity. So depending on your symptoms, your blood work, and your blood pressures, those things together help us say, “Is this a severe form of preeclampsia?” and if it is, then we usually have some specific things that we have to do. 

Generally, you likely are monitored in the hospital. We keep a close eye on your blood pressure and your organs. That pregnancy is considered to be very high risk. Very high risk for a harm for mom, so risk of seizures, impact on the organs that can sometimes be lifelong and risk to baby. The highest risk to baby is that risk of being born early, so pre-term delivery. And usually if you have severe preeclampsia, we usually recommend delivery no later than 34 weeks. So once we do develop that severe form, we keep a close eye on things. 

If you have the non-severe form, so if your organs look oay and your blood pressures are stable but you have some protein in your urine and we do think you have preeclampsia but it’s not severe, then we give you some more time. We still monitor you and baby very closely, but we can maybe try to get the pregnancy up until 37 weeks and after that, the risk of continuing the pregnancy and harm to maybe the mom and baby are a bit higher than some of the risks of being born at 37 weeks. So at that time is when we would say, “Let’s have a birthday.” It really depends on those things. 

Meagan: Okay, that’s so good to know. I think sometimes that also can vary like, I’ve got high blood pressure, but I don’t have protein. Or I’ve got a trace of protein but I’m doing okay, I don’t have any symptoms. But we also know with preeclampsia it is important to watch really closely no matter whether severe or not because it can turn quickly. Where you have zero signs and the next morning and you wake up with a headache and crazy swelling and you have that blurred vision with really high numbers. So it’s just really important to watch.

Dr. Pinnock: Exactly.

20:46 HELLP Syndrome

Meagan: I really do like to ask that question because a lot of people ask, do I have to have a C-section? Do I have to be induced? What does that mean? Am I severe or not severe? And we also note, we weren’t even talking about this, but HELLP syndrome. So we can develop more, right? Preeclampsia affects more the mom, but then alsothe  baby timewise. HELLP syndrome is another really high-risk complication. What would you suggest for that when it comes to TOLAC because we have platelets being affected there? That one is a tricky, tricky one. 

Dr. Pinnock: I think HELLP syndrome is on that same spectrum of hypertensive disorders in pregnancy. But HELLP syndrome can be pretty life-threatening and dangerous for mom and by extension baby. So HELLP syndrome is when we find that your body’s sort of hemolyzing so there are some things in your blood that’s causing your blood vessels to sort of open red blood cells. We find also that you have elevated liver enzymes so your liver’s being impacted pretty severely and then the platelets or the blood cells that help with clotting get really, really low. And so the combination of that with or without elevated blood pressures make us very concerned about HELLP. So the worry is if we don’t deliver the baby pretty expeditiously and deliver the placenta which is thought to be really the source of the diagnosis, mom can get really ill and we really try to deliver as soon as possible. 

The exact way we deliver is really dependent on the specifics of what is going on. So maybe if your liver enzymes are very, very elevated and there's a high concern for mom’s health and safety, your doctor may say, “I don't think we have time to try for a TOLAC, especially if you're not in labor. I think it would be too unsafe. I think I would recommend a C-section at this time because of that,” then that would be that recommendation. 

Sometimes we do try for a vaginal birth with HELLP, but it would be a case where we would want to limit how long we try but overall we try to deliver as fast as possible either vaginally or with a C-section. And if you do want to try for a TOLAC in that setting, I think my recommendation is to really, really be open to whatever is best for your health and your babys health. That’s my advice for all women who are in labor. 

It’s such an unpredictable experience and you can come in with your desires and your doctor can come in with their desires for you, and your baby or your health just dictates something else. And so with HELLP, that’s an even more significant moment where if your body’s telling us one thing, we have to listen. You may not be eligible for a TOLAC at that point. I think in more cases than not, many providers may not have that bandwidth or think it’s safe to try for TOLAC in that setting. 

Meagan: Yeah. I’ve had very few clients as a doula who have had HELLP, but one of the clients– they actually both ended up having a Cesarean, but one of the clients’ providers was even uncomfortable with even having an epidural and actually suggested general anesthesia. Is that a common thing if HELLP is super severe that could possibly be what’s suggested or best?

Dr. Pinnock: Yeah, no as I mentioned with that kind of diagnosis, you can have pretty low platelets. And so when we think about a procedure like an epidural or even a spinal, so any sort of neuraxial anesthesia where we’re not putting mom to sleep, we’re just numbing mom from the waist down, that requires insertion of a needle or a catheter in the back. That’s near a lot of important structures so once you have that puncture, you’re going to have some bleeding. And if those platelets aren’t enough to sort of prevent that bleeding from extending, then our anesthesia team may not be comfortable doing that procedure safely because it’s not safe. 

They may offer to give some platelets etc but often with HELLP, it may not be as fast acting and sometimes you may just hemolyze again. Those platelets may go back to being very low and if we are thinking about having a delivery urgently, delaying for that reason may not be safe for mom and baby. Oftentimes, if the platelets are too low, then our anesthesia colleagues, who are a very important part of the team, may recommend against trying for an epidural or even a spinal and recommend general anestheia.

In my experience, I don’t do C-sections under general anesthesia often, but when I do, it’s usually recommended for a very, very significant reason and it’s always with the safety of mom and baby in mind. It’s never something that we want to do. It’s only something that we do if we have to do for mom’s safety or for baby’s safety. 

Meagan: Yeah. So good to know. And they actually ended up doing a platelet transfusion as well specifically for the Cesarean. Obviously, we know blood loss is a thing that’s a big surgery so they were trying to help her there. 

26:36 Other High-risk situations

Meagan: Okay, well are there any other high-risk scenarios where you feel like truly impact the ability to have a TOLAC offered?

Dr. Pinnock: Yeah. I think the highest risk conditions that could prevent mom from having a TOLAC are probably conditions related to the heart or lungs where the physiology or the changes that happen in labor can make it so that a vaginal birth is not safe or recommended for mom or baby. 

A TOLAC in those high-risk settings is often not recommended. There are a lot of cardiac and lung conditions that we take care of. There are not that many that we would say you can’t have a vaginal birth, but sometimes there are blood vessels in the heart that can be dilated or blood vessels near the heart that can be dilated that we may say, “No, you definitely need a C-section,” so if you wanted to TOLAC we wouldn’t recommend that. Those are probably the highest-risk conditions that I take care of and where a TOLAC is not recommended or even offered because it’s just not considered to be safe. 

27:54 Gestational Diabetes

Meagan: Okay that’s so good to know. Okay, let’s jump in a little bit to gestational diabetes. We can have both managed and not managed. Do you have any advice for listeners who may have gestational diabetes or maybe had gestational diabetes last time and they’re preparing to become pregnant or wanting to learn more about how to avoid it if possible or anything like that? Do you have any suggestions to the listeners?

Dr. Pinnock: Yeah, that is one of my favorite things. I really believe that just paying close attention to your health and taking steps before pregnancy can make a world of a difference in your risk of developing certain conditions. Gestational diabetes is one of those conditions that can be definitely most susceptible to things that we can do before pregnancy. 

And so I know that this is going to maybe sound like a broken record to those who had gestational diabetes before, but just look at your lifestyle factors. I think that the most undervalued or underestimated intervention is really exercise. It doesn’t have to be your training for an Iron Man or a marathon. It could just be like a 20-minute walk every day or a ten-minute job every day and work your way up. We definitely found that aerobic exercise more days of the week than not, and resistance training, it could be with resistant bands, if you have any sort of light weights or even body weight. Any resistance training to help build up that muscle mass can help to reduce your risk of getting gestational diabetes. 

If you couple that with adjusting your diet, and diet is such a big topic but essentially no matter what your background is, focusing on the whole foods of your cultural background is best. So low processed foods, more homecooked meals with whole grains, fruits, vegetables, fish, and limitations of red meat and processed foods. All of those things can go a long way with preventing gestational diabetes and also reducing the recurrence of gestational diabetes. I’m really passionate about that. 

Meagan: Yeah, us too. I didn’t have gestational diabetes, I had kidney stones weirdly enough because my body metabolizes nutrients differently during pregnancy and anyway, it’s totally not gestational diabetes but I had to look at my pregnancies and before as something like that. Really dialing in on nutrition. Really dialing in on my exercise. And I couldn’t agree more with you that it doesn’t have to be this big overwhelming Iron Man training or running a marathon. 

It really can be a casual 20, 30-minute stroll around the neighborhood walking the dog or whatever and dialing in on those whole foods. We love the book Real Food for Gestational Diabetes by Lily Nichols. If you haven’t ever heard of that, it’s amazing. It’s a really great one. You might love it. And I definitely suggest that to all of my clients. She even has one for Real Food During Pregnancy. Just eating good food and then we love Needed because we know that getting our protein and getting the nutrients that wer eally need can really help like you said recurring and current and just avoiding hopefully. So we really love that topic, too. 

But gestational diabetes doesn’t just nix the opportunity to TOLAC, correct?

Dr. Pinnock: No, it doesn’t. Gestational diabetes can be a really tough diagnosis for a lot of women to get in pregnancy. It can be really disappointing especially if you may be a relatively healthy, active person and you don’t have a lot of risk factors for developing gestational diabetes. It can kind of feel like a gut punch almost. 

Meagan: Yeah! And it’s very overwhelming because you’re like, What? No! 

Dr. Pinnock: It is! And it happens fast. You’re diagnosed and then you have a flurry of things that you have to now do and change and think about. It can be very stressful. But I always tell my patients that there are things that put some people at risk of developing gestational diabetes more than others, but all women because of those placenta hormones can have insulin resistance or your body’s just not responding as well to the insulin that you’re making. 

Depending on those risk factors, some women develop it. Some women don’t. And once you do develop gestational diabetes, it’s something that we really pay attention to because it can increase the risk of things for moms so particularly it can increase the risk of mom developing preeclampsia and it can increase the risk of things for baby. Babies can be on the bigger side or have macrosomia if the blood sugars are too high. 

They can actually have a higher risk of having a birth injury if we’re having a vaginal birth or mom may actually have a higher risk of needing a C-section if you’re trying to TOLAC and baby’s on the bigger side. Rarely, and this is sort of the thing we worry about the most, is that if those blood sugars are too high for too long, baby can be in distress on the inside and it can increase the risk of having a stillbirth or having baby pass away. 

So because of those things, once we diagnose it, we do pay attention to it and we try our best to sort of make those changes hopefully with diet and exercise to sort of manage the blood sugars. If we’re having perfect blood sugars with those changes, then wonderful. If we’re not, and it happens and you need some additional support then your doctor provider may recommend some other management options like medications to help to bring the blood sugars down. 

But I think, when we think about TOLAC, we want to think about separately managing the pregnancy, keeping mom and baby safe, and then thinking about the safety of delivery. So as long as the baby’s size isn’t too big, as long as mom and baby are healthy and safe, you can definitely try for TOLAC with gestational diabetes. But those two things are big “buts”. You really want to try your best to manage your blood sugars so baby’s size doesn’t work against your efforts of trying to have a TOLAC.

35:00 Inductions with gestational diabetes

Meagan: Yeah, we know that the size can definitely impact providers’ suggestions or comfortablity to offer TOLAC. And we know big babies come out all of the time, but we know sometimes there’s some more risk like you were saying. So can we talk to the point of inductions?

So a lot of providers will, and you kind of touched on it. There can be an increased risk of stillbirth. But a lot of providers seem to be suggesting that induction happens at 39 weeks. Some of the evidence shows that in a controlled situation, meaning all of the sugars are controlled, but what do you see and what do you suggest when someone is wanting a TOLAC, has gestational diabetes, may have a baby measuring larger or may have a provider who is uncomfortable with induction which we see all the time? Any suggestion there and what do you guys do over in your place of work?

Dr. Pinnock: Yeah, that’s a great question and it’s something that I individualize to every patient. So let’s think about it in two different buckets or three different buckets. Say you have gestational diabetes that’s pretty well controlled with just diet. So with diet and exercise, your numbers are pristine. Baby is a good size, we’re not over that 4500-gram mark where we start to say, “Is it really safe to try for a vaginal birth?” and that’s okay. If we are in that boat, then I think it’s reasonable to allow for mom to go into labor and try for TOLAC if that’s their desire. 

The exact gestational age at which someone goes into labor varies. We don’t have a crystal ball. We don’t know. 

Meagan: Nope.

Dr. Pinnock: We do have to balance waiting for that labor process with the inherent risk of babies being less happy and distressed and the risk for a stillbirth as the pregnancy progresses. Now, if you have gestational diabetes that’s well controlled with diet, we think from the studies that we have that our risk of stillbirth is similar to someone who does not have gestational diabetes which is good. And so for those pregnancies, depending on your specific location and provider, we may do some monitoring with non-stress tests or something like that later in the pregnancy until you deliver. Usually, we start at around 36 weeks or so if you’re well-controlled with just the diet and allow you time for your body to go into labor and have a vaginal birth. 

Now, if we get to your due date and nothing, baby is still comfortable inside. They’re like, Oh no. I’m just hanging out, we start to think, How long are we going to allow this to go on? At that length of time, we start thinking about, Okay. We’re at 40 weeks. What are the risks to mom and baby? And so at 40 weeks, we’re about a week past 39, and we know that the risk of– if things are perfect for anyone, the risk of having babies be in distress, maybe the placenta’s just been working for a long time and isn’t just working as well and the risk of stillbirth goes up, we don’t want to go to 42 weeks. 

So I think at that moment, it’s a good time to think of an exit strategy. If your baby is just so comfy on the inside, think about, when I would say is an upper limit of reasonablility to wait for labor? That varies depending on the person and provider. But I think reasonably, up until 41 weeks. I wouldn’t go past that. If we’re allowing our body to go into labor up until 41 weeks, then we have to think about, How does that impact my risk of having a successful TOLAC? After 40 weeks, some of our studies suggest that you may be at a higher risk of having a failed TOLAC or needing a C-section and that’s regardless of whether you're induced or whether you go into labor. TOLAC-ing does carry that inherent risk so it’s really just dependent on your doctor, you,  your provider, and balancing all of those things. I think going until 41 weeks is probably the maximum limit for a well-controlled gestational diabetes with perfect sugars, no medications, and we’re still doing monitoring to make sure that baby is doing well.

Now, if you’re in the camp where you’re either gestational diabetes, or even controlled with diet, or if your gestational diabetes is controlled with medication or if you’re diet-controlled, but those sugars aren’t great, any scenario where the sugars aren’t perfect and we need either medications or your sugars aren’t perfect, I don’t generally go past 39 weeks.

The reason being at 39 weeks, baby is fully developed and after that, the risk of having a  pregnancy loss goes up because of that uncontrolled or not optimally controlled gestational diabetes. I think at that gestational age you would want to think about maybe an induction or maybe a repeat C-section depending on how you’re feeling if your body isn’t going into labor. And that’s a personal decision. 

Now, if you have gestational diabetes managed with medication and your baby is big and maybe let’s say over 4500 grams which is sort of that range where we worry about the safety of a vaginal birth. And you’re now going into labor, then that becomes a little bit more of a shared decision-making where you want to think of, My baby’s big. I would need to be induced. Is this going to be something I want to commit to or is it something I don’t want to commit to? That’s a personal choice but I think at that gestational age I would say I wouldn’t want anymore. 

ACOG though does recommend or does allow for moms who do have gestational diabetes well controlled with medication, like if your blood sugars are perfect with the medication to go until 39 weeks and 6 days. So technically you can use those extra few days, according to our governing board or the American College of OBGYN. But it’s going to really come down to you and the relationship you have with your doctor and what you both are comfortable with. Maybe you have a provider that is open to that recommendation or a provider whose more open or comfortable to a 39-week delivery regardless of how well your blood sugars are controlled once you’re on medication. But ACOG does give us that wiggle room to say we can go further. 

42:25 Fibroids

Meagan: So good to know. Okay, let’s see. Is there anything else we would like to talk about high-risk-wise? I know I had mentioned one time about fibroids and heart-shaped uterus. Do you have anything to share on those two topics, because those are also common questions? Can I TOLAC with fibroids? Can I TOLAC if I have a heart-shaped uterus? Where does that land as VBAC-hopeful moms?

Dr. Pinnock: Yeah, no. I think those are some great things to consider. So I think we can open with the fibroids. I think if you’ve have had fibroids and you’ve had that fibroid removed, so you’ve had a myomectomy, there are a handful of things where we usually say, “No, we don’t want you to TOLAC.” One of them is if you've had a previous uterine rupture or that previous Cesarean scar opened in a previous delivery, that’s an absolute no. The risk is too high. We don’t think it’s safe. The other is if you’ve had a previous surgery where that surgery included the fundus or the top of the uterus where those contractile muscles are. Usually, with a myomectomy or fibroid removal, that involves that area. If you’ve had a fibroid removed in that area or you’ve had a myomectomy, a TOLAC is not recommended. So those are sort of one of the few things or few times where we say, “Absolutely, no.” 

If you have a fibroid and maybe you just discovered you had it during pregnancy, most of the time fibroids don’t cause any problems. They’re benign growths of the muscle of the uterus that can vary in size. So generally if they’re small to medium size and depending on their location they may not cause any problems. If they do cause a problem, the most common thing women experience is pain. But usually if they’re not too big and they’re not in a location where we’re concerned about, it should not really your ability to TOLAC. 

Now if the fibroid is like 10 centimeters and located near the lower uterine segment or the part of the uterus where the baby transports through to come out through the vagina, then we’re going to take a pause and say, “Is this going to be a successful TOLAC?” Is the fibroid going to compete too much with the baby’s head for baby to come down safely and should we just think about doing a C-section? And a C-section in that event is also not straightforward or a walk in the park because either way, the fibroid is present near where we would use to deliver the baby.

 So short answer is that yes, you can TOLAC with a fibroid. But the long answer is that it really depends on how big the fibroid is, where it’s located and whether we think it’s going to obstruct that area where baby’s going to come from. If it’s not, then it’s reasonable to try and many women have TOLAC’d with fibroids all the time. So it’s definitely not a reason to say, “No, you definitely can’t.” If you’ve had the fibroid removed though, then it’s a no. That’s just one thing to talk about if you’re considering that procedure and you have an opportunity to talk with the provider who is offering that procedure, just knowing that after that for most surgeries that remove the fibroids you won’t be able to try for a vaginal birth. 

46:33 Do fibroids tend to grow during pregnancy? 

Meagan: Good to know. Good to know. And is it common for fibroids to grow during pregnancy? Does pregnancy stem them to grow? Or does that impede them because you’ve got a baby growing in there and the focus is on growing a human and not growing a fibroid?

Dr. Pinnock: No, that’s a good question. Interestingly enough, we see about a split group so about a third of them stay the same. They don’t change in size. A third of them shrink and a third of them grow. 

Meagan: Oh wow.

Dr. Pinnock: We don’t know which third it will be. Two-thirds of them either get smaller or stay the same size. But there are women who experience growth of the fibroid and it’s actually due to those hormones estrogen, progesterone, and all of those hormones being released by the placenta. It stimulates the fibroid to grow and that’s actually when some women experience pain. 

The fibroid grows. It outgrows its blood supply and then it degenerates or dies off a little bit and it causes this pretty significant pain for some women, but interestingly it’s not 100%. A lot of people don’t have many symptoms and don’t have any pain. When I monitor fibroids, a lot of them don’t change in size. Some of them get smaller and sometimes I’m not able to see them later on because they’re so small. But there is that percentage who experience the growth of their fibroid and that’s usually when pain is experienced from them. 

Meagan: Okay. And you mentioned that they could. I mean, 10 centimeters is a pretty large fibroid but it can happen, right?

Dr. Pinnock: I’ve seen it. 

Meagan: Yeah, so it can happen. You said it can compete with baby coming down. Can fibroids also inhibit dilation at all? Can it impact dilation at all?

Dr. Pinnock: Absolutely. Some of the things that we see or that we worry about if there’s a large fibroid present is other than impacting the area where baby can come through, it can cause dysfunctional labors. So those muscles that are contracting in a uniform way aren’t going to be able to contract as uniformly as they would have if the fibroid wasn’t there. So sometimes the labor can stall. The cervix isn’t dilated as much. Even sometimes we see that fibroid causing babies to actually present head down and so that’s also something that we can see with very large fibroids. It can actually increase the risk of baby being breech or transverse or malpresenting in general. 

Meagan: interesting. And you said that sometimes there aren’t even any symptoms at all, so how would one find out if they do? Is that just usually found at 20-week ultrasound? Or is it possible that at 20 weeks you had it but it’s so minute and it’s so small, that you can’t even see it? And then in labor we have some of these symptoms or whatever and it’s there but we don’t know?

Dr. Pinnock: Not usually. Most women, if they didn’t know they had a fibroid before pregnancy, get diagnosed in pregnancy at an ultrasound. Either a first trimester or 20-week ultrasound, we look at the uterus in detail and we can pick up fibroids. We are hopefully not going to have a 10-centimeter fibroid present at 10 weeks that’s missed that’s just going to magically present at 39 weeks and be a surprise. Usually the fibroid, if it’s there, is picked up on an ultrasound. That’s the most common way it’s picked up. Depending on the size, it may be a reason why your doctor or provider recommends for you to have ultrasounds in the pregnancy. 

Sometimes we monitor the fibroids. We monitor their locations, the size of them, and we make sure that they’re not too big to be causing a problem. Rarely if they grow, they don’t usually grow from like 3 centimeters to 10 centimeters. They may grow a centimeter or two. It’s very unusual to have that big change. And so for the most part, it’s picked up on ultrasound. We know the size of it. If it grows, it grows a small amount. It’s not going to grow from 5 to 10, and we’re going to know the location of it from that first time we evaluate it. It’s not going to be a surprise moment at delivery where we’re like, Oh my goodness, this wasn’t picked up.

51:20 Bicornuate Uterus

Meagan: Okay, good to know. Good to know. Okay and last but not least, I know we’re running short on time and I want to make sure we respect that. Any information you have on a heart-shaped uterus? Is TOLAC possible with heart shaped uterus? Have you seen it? Have you done it?

Dr. Pinnock: I have not seen it or done it to be honest. I do think a heart-shaped uterus just so we’re using the same language that’s considered a bicornuate uterus, is that–?

Meagan: Yes, a bicornuate uterus.

Dr. Pinnock: So for a bicornuate uterus or any kind of situations where the uterus developed differently, interestingly the uterus develops from two different stuctures. It develops from something called the Mullerian Duct and early in development when you are a tiny, tiny baby, those two structures fuse and when they fuse, they come side by side first, and then they fuse. When they fuse there, is a little wall in the middle that gets removed and so when all of that is done you have uterus that is shaped as we know it and we have that cavity on the inside where the baby would come in and grow. 

Now with a heart-shaped uterus, or a bicornuate uterus, there is an error when those structures come together side-by-side. So sometimes they just stay side-by-side and they don’t fuse as well or sometimes they fuse but only fuse partially. So you have the uterus that as we know it, but sometimes you can have two separate structures. So two separate cavities where the prgenancy can grow, or you can have one cavity where there is still some tissue right in the middle there. It can vary depending on the suffix of how that fusion happened. 

Essentially, if there’s less space in the cavity either from that tissue or having two separate but smaller cavities, there’s presumably less space there for baby to grow. There’s less contractile strength on that one side and so it can theoretically increase the risk of certain things happening in labor. I think the things that we see most commonly with bicornuate uteruses, it can have a higher risk of having a pregnancy loss, so a miscarriage. High risk of baby being born early because that area is just smaller so it’s not as strong in holding the pregnancy. And similarly, baby can also be malpresented more commonly because the are is much smaller than a full uterine cavity.

Meagan: That’s what we see a lot is breech. 

Dr. Pinnock: Exactly. I haven’t seen too many cases. It’s a rare thing to see. I haven’t seen too many cases where baby’s head-down and we’re at full-term and wanting a TOLAC. A lot of cases I’ve had, baby is breech or malpresenting so we end up doing a C-section. The shape of the uterus is not going to change for the next pregnancy so chances are the baby’s usually malpresenting. 

I don’t think we have any big databases or big data to say is it safe? Is it not safe to TOLAC? I think the main thing you’d be concerned about it that spontaneous uterine rupture if there is labor going on even if you haven’t had a C-section and also if you’ve had a C-section before. So I think a TOLAC would be a little bit of an unknown for this situation. I would think on it pretty heavily and talk with your doctor about the specifics of your situation. If your previous C-section because baby was breech, chances are baby’s not going to be presenting head down because of the shape of the uterus. It tends to have things that recur as to reasons for having a C-section. So we don’t have any large databases where we have women who have TOLAC’d with this condition, so hard to say. So maybe give it a try, but maybe thing long on this one. 

Meagan: Case by case, it all comes down to case by case.

Dr. Pinnock: Yes. That’s pretty much what I do. Anything in pregnancy that’s a little bit more nuanced and any high-risk condition, it’s very individualized. And we have to really have that approach with high-risk pregnancies or anything that comes up that makes your pregnancy higher risk of having anything happen to mom and baby for sure. 

Meagan: Right. Oh my goodness. Well, I love this episode so much and cannot wait to hear what people think about it. I’m sure they’re going to love it just like I do. I know I mentioned at the beginning of your podcast and things like that, but can you tell us more? Tell us more about the ZerotoFour podcast and where people can find you. I know you have YouTube and all the things, so tell us where listeners can follow you.

Dr. Pinnock: Yeah. You can find me on Instagram @drchristinapinnock, the ZerotoFour Podcast so the where I share the episodes with new moms about pregnancy. I really started the podcast with the goal of helping moms to be more informed and comfortable about everything along their pregnancy journey. I share topics from the whole spectrum of that journey to help you feel more prepared and informed and empowered about your pregnancy experience. You can find episodes there, on Apple Podcasts, Spotify, or anywhere that you listen to podcasts.

Meagan: Awesome. So important. This is a VBAC-specific topic, but I mean those first-time moms, we have to learn. We have to learn all the things because there is really so much. We just talked about a little nugget of a couple of high-risk situations and there’s just so much out there that can happen. It’s so good to know as much as you can. Get informed. Learn all the things. Follow your podcast. I definitely suggest it. We’ll have all the links in the show notes and thank you for joining us today. 

Dr. Pinnock: Thank you so much for having me. It’s been a pleasure. 


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