“Hypertension during and after delivery” – with Dr. Samantha Do

Dr. Fox: Welcome to today’s episode of “Healthful Woman,” a podcast designed to explore topics in women’s health at all stages of life. I’m your host, Dr. Nathan Fox, an OB/GYN and maternal-fetal medicine specialist practicing in New York City. At “Healthful Woman,” I speak with leaders in the field to help you learn more about women’s health, pregnancy, and wellness. All right, Dr. Samantha Doe, welcome back to the podcast. How goes it?

Dr. Do: Thanks for having me back. Goes well.

Dr. Fox: Thanks for having you back. Thanks for coming. This is terrific. So, we’re going to be talking today about hypertension or high blood pressure, but we’re going to be talking specifically about high blood pressure during and after delivery. So, I guess I would ask you, how common is this?

Dr. Do: Pretty common. The literature suggests it’s not that common, but I feel like we see it all of the time. We say 2% to 8% of pregnancies have gestational hypertension or preeclampsia, kind of pregnancy-induced hypertension, and chronic hypertension is on the rise in America. So, we’re seeing it more and more kind of more than the baseline 1% to 2% that people talk about.

Dr. Fox: Yeah, and I think that what happens is a lot of people during their prenatal care, coming into pregnancy or during pregnancy, when their blood pressure goes up, they sort of like, they get it, they get a diagnosis, they talk about it, you have a plan for it, you do this, you do that. But when someone doesn’t have that and they show up in labor and then in labor, their blood pressure goes up or right after they deliver, their blood pressure goes up. And so on our end, we’re doing the same things, but I feel like on the patient side, they don’t always get that processing, that conversation about it. And there’s like, “What my blood pressure is high?” because there’s so much else that’s going on at that time. And I think people don’t realize that that’s something that can happen, that they’ve never had it in their life and then suddenly, in labor, their blood pressure is high and we’re talking about it and coming up with a plan after delivery.

Dr. Do: Yeah. And the question is, does high blood pressure stimulate labor? Does labor stimulate high blood pressure? But it is something that comes up all the time, especially since we’re doing so much more monitoring of blood pressures in labor.

Dr. Fox: Yeah, it is a really… I mean, you asked a really fascinating question, and they happen together a lot. Someone’s in labor and their blood pressure is up. And we really haven’t figured out why is it more common in labor than two weeks before labor, right? So, if you have two people who are, let’s say, 39 weeks pregnant, one’s in labor, one’s not in labor, the one in labor is more likely to have hypertension. And it’s not really clear as it’s sort of like, “Well, you get hypertension and somehow your body realizes that’s not great. Maybe it’s time to go into labor and finish the pregnancy,” which would be wonderful, but we haven’t really mapped that out. Does that happen? If so, how does it happen? Or, is there something about the uterus contracting and squeezing the placenta? Again, these are all sort of hypothetical situations or possible reasons. Does that cause preeclampsia or high blood pressure? And we don’t really know, but it’s definitely true. You’re more likely to have high blood pressure in labor than you are the week or two before labor for some reason. And so that that definitely comes up for people who never had it before. But you could also know you have high blood pressure and come into pregnancy and have it during labor and delivery and it could potentially get worse, right?

Dr. Do: Oh, definitely something we’re looking out for always.

Dr. Fox: Yeah. So, we have in general, just like as an overview… And you mentioned these things before, but just to review for our listeners who may not be caught up to date, high blood pressure means your blood pressure is high. But we sort of, in our world, categorize it based on sort of the story behind the high blood pressure. So, how do we categorize people with high blood pressure in pregnancy?

Dr. Do: We think about… If you have a story of high blood pressure before pregnancy or the first half of pregnancy before 20 weeks, we’d find that as chronic hypertension or, kind of, you have a baseline predisposition to high blood pressures. That might be something you know about before pregnancy, if you’ve seen a doctor or might be something gets diagnosed for the first time in pregnancy when you’re seeing a doctor more regularly in the first half of pregnancy. And we think about that set of risks a little bit differently for what happens in both pregnancy and around the time of delivery. Then kind of you have new onset blood pressure. So, we contrast that kind of first half of pregnancy, pre-pregnancy, high blood pressure, chronic hypertension with blood pressures that are newly elevated in the second half of pregnancy. And we call that either gestational hypertension or preeclampsia, depending on the severity of it. We think of it as a spectrum. And that second half of pregnancy often happens really late in pregnancy. The farther you go, the more risk you have of it coming up, even if you’re low risk for it. So, more common at 41 weeks than at 39 weeks to have that high blood pressure in pregnancy.

Dr. Fox: Right. So, whether someone has chronic hypertension and again, like you said, knows about it coming into pregnancy or finds out about it early in pregnancy, which is always a fun conversation, or they don’t have it and they develop this gestational hypertension, preeclampsia. All of those people, when they come into labor, know that they have it or, in fact, we might even be inducing them because they have it, like saying it’s time to deliver. So, there’s that group of people, sort of the ones who, “I know I have high blood pressure for whatever reason I’m dealing with that we’re talking about it. I’m getting induced for it or I’m in labor,” fine. And then there’s a group we talked about before that had none of this and it just shows up during labor and delivery. But all those people together is what we’re talking about today. Anybody who has high blood pressure and they’re around the time of labor, delivery, and a little bit postpartum. So, we have all of these people, they’re in labor. What do we do differently, let’s say, for someone in labor? What might they experience that’s different compared to someone who does not have high blood pressure in labor?

Dr. Do: So, we’re going to be paying attention more to their blood pressures, we pay attention to everyone’s, but even more vigilantly. They’re going to get blood work done to look and see if there’s things that can change with high blood pressure of pregnancy because of hormones that are released in the placenta. It can affect not just the blood pressures when it’s high blood pressure of pregnancy. It can also affect the kidneys and the liver, the clotting factors, so we look at those in labor. And we’re going to treat their blood pressures to make sure they’re not too high with blood pressure medications. And some of the women who have blood pressures that are high before pregnancy that they know about for a long time will be on blood pressure medications and will continue those through the labor and delivery course. Sometimes people have newly elevated blood pressures where they’re going to need blood pressure medications acutely in the moment during labor and delivery.

Dr. Fox: Right. So, someone’s in labor and you say we do blood work. Everyone pretty much coming… At least in our hospital, everyone who shows up in labor is going to get blood work. So, they probably wouldn’t notice that that’s something we do, but most people would be oblivious to that. In terms of their blood pressures, would someone in labor, other than seeing the number on the machine, know that they have high blood pressure? Would they feel any different in labor typically if their blood pressure is a little bit high versus normal?

Dr. Do: Exactly. You’re saying often they wouldn’t feel anything different if their blood pressure is a little bit high. Sometimes it can be associated with other symptoms, like feeling like they have headaches that won’t go away or, kind of, changes in their vision or, kind of, pain on their upper right side of their abdomen. But usually they’d be not feeling anything with the blood pressure as being high in the mildly elevated range.

Dr. Fox: Right. The interesting thing is I would say, for most people, when they have symptoms related to their blood pressure, it’s the opposite. When their blood pressure drops—like in labor, sometimes after getting an epidural—it can make them feel pretty lightheaded, sometimes nauseous, and sometimes even vomit. But high blood pressure? Not so much. And how do we decide on our end if we’re going to give medicine in order to lower the blood pressure versus just, sort of, let it ride?

Dr. Do: Yeah, it depends what people’s baseline is and, kind of, how high the blood pressures are and what their risk is based on how high they are. So, if they are on blood pressure medication, kind of oral medication that they take at home, we’ll just continue those. If they have newly elevated blood pressures that are severely high, we think 160 for the top number, the systolic, or 110 for the bottom number, the diastolic, that’s where it’s more risk for moms to have those blood pressures that high. And we’d recommend giving medication.

Dr. Fox: Right. And then it is true that a lot of the women who have sort of, let’s say, high or nearing that range, we would treat it. It does work out coincidentally that if they get an epidural, it frequently lowers their blood pressure because an epidural, sort of, naturally…not naturally but it does lower people’s blood pressure. So, that might avoid it. It’s not the treatment we use to lower someone’s blood pressure, but it might avoid. But I would say for most people, they won’t care, so to speak, if they’re getting medicine for their blood pressure or not, because there don’t tend to be ton of side effects. So, this is really just to keep them safe during labor. Now, what about their actual labor course? Is someone with high blood pressure, is their labor going to be easier, harder, longer, shorter, more painful contractions, less painful contractions? Is there any difference to them? Will they notice their labor being different because of that?

Dr. Do: It shouldn’t make contractions more painful or less painful. There’s some data that maybe people who have high blood pressure, kind of, long-term high blood pressure might have a little bit slower laborers than people who don’t have long-term high blood pressure. There’s been some debate about whether having, kind of, blood pressures that are high because of pregnancy makes labor spit up because they want the baby out. But probably on balance, it’s going to be a similar duration.

Dr. Fox: Yeah. And then so far, it seems like most people wouldn’t know the difference, right? They’re getting blood work anyways, so unless they’re looking up their results, they wouldn’t know. They wouldn’t notice their blood pressure is high typically, though they could. They probably won’t notice either way. If they’re getting medicine for blood pressure, labor is going to be the same. So, what would be the main difference for someone in labor with high blood pressure compared to someone without that they would be cognizant of or they would notice?

Dr. Do: One of the big things, if the blood pressures are severely elevated, kind of, in the 160 or 110 range that we talked about, then they might need magnesium if they’re, kind of, in that severely elevated range and pregnancy-induced hypertension, high blood pressure because of pregnancy. And that’s to decrease the risk of seizures that goes with that pregnancy-induced hypertension picture where regular, kind of, high blood pressure we don’t think is associated with seizures. Can you have high blood pressure just because you have it long-term? But when you have it because of these hormones, the bloodstream from pregnancy, that it can induce the risk of seizures. And so people get magnesium, which is a really safe medication for decreasing risk of seizures and the most effective one for that, but comes with some bad side effect profiles that moms will notice.

Dr. Fox: Right. So, let’s talk about that. So, magnesium is given intravenously. So, it’s given through an IV drip. And what do moms who are getting it typically feel?

Dr. Do: They feel almost like they have the flu. They feel warm. They feel hot. They feel tired, especially in the first 30 minutes where they get, kind of, a concentrated amount of the infusion and then get a low dose of it, kind of, a maintenance infusion after that through the IV drip. So, they usually feel not quite as bad for that part of it than, kind of, the first part, the onset of it.

Dr. Fox: Yeah. And that’s typically, sort of, the deal breaker for people, whether they notice it or not. And it’s usually something… We’re taking history for someone and they said, “I had high blood pressure and labor.” Usually the question we’re going to ask to figure out how severe it is is, “Did you get magnesium?” And the answer is, “Yes.” It was probably pretty severe. And it’s unusual that people don’t know if they got magnesium or not. If they don’t know, they probably didn’t get it because… Not everybody. There are some people who get magnesium and don’t have side effects. They’re the very lucky ones. I would say most people do have side effects, but it’s a tradeoff because the alternative is not as safe because you can’t go through labor with severely high blood pressures because you absolutely could seize or have bad things happen. So, we, sort of, have to do it. And then one of the other negatives of magnesium is when do we stop it?

Dr. Do: We like to continue it for the high-risk time of seizures, which is in labor and for about 24 hours postpartum. So, you get it both during labor and after delivery, which then makes that early postpartum period harder.

Dr. Fox: Yeah. And we can sometimes stop it earlier than 24 hours, but if anyone is getting magnesium in labor, I would say the expectation is you’re going to get it for 24 hours after you deliver. And occasionally based on a lot of factors, it might be stopped a little bit early, but assume it’s going to be 24 hours. And that is definitely a bummer. It’s just harder to function and you have to stay in bed pretty much. And you don’t feel great in it. It doesn’t delay your recovery, but it delays you feeling normal for a little time. Will having high blood pressure during labor make you stay in the hospital longer after delivery?

Dr. Do: It’s something that certainly can, because we know that as your body is mobilizing some of the fluid after delivery, your blood pressure is going to go up after delivery even more. And so we want to watch closely what your blood pressures are after delivery. And that can mean a little bit of a longer stay in the hospital and also early follow-up postpartum in the office.

Dr. Fox: Right. So, the one thing I want to ask you about, because we didn’t talk about this yet, is there are people who their blood pressure is normal in pregnancy, it’s normal when they’re in labor, it’s normal when they deliver and then it goes up after they deliver. So, why does that happen? What’s up with that?

Dr. Do: Yeah, that seems unfair because we think the blood pressure that’s high because of pregnancy is mediated by the placenta at delivery. Baby delivers and the placenta delivers. But there are still some hormones in the bloodstream that take a while to wash out, to, kind of, get diluted and go away. And so for some women, we don’t see it until after delivery, that postpartum hypertension. And we think about them similarly. We watch them closely. We do similar things that we do in labor. We know it’s going to go away, but we still want to take care of moms with it.

Dr. Fox: Yeah. I mean, that’s one of the reasons that preeclampsia and high blood pressure can be so dangerous, because if we know about it and we’re looking at it and we’re treating it, it’s unusual that something horrible is going to happen, right, because we’re usually on top of it. The time when it really can be a big issue is if it’s unrecognized. And so, like you said, most people don’t have symptoms if their blood pressure is high and some do but most don’t. And if you’ve already delivered and you’re in the hospital, we can pick it up because that’s why we check blood pressure. People are like, “Why are they checking my blood pressure every four hours? I’ve already delivered the baby. I feel fine.” We’re looking for this and then people go home, right? And so if it hasn’t been diagnosed, it can even come as late as you’re already at home. And there’s a lot of debate about what to do about that, right? Should everybody be checking their blood pressure at home routinely? And if so, how and how those results are going to get in? Should it only be higher risk women who do that? Should it be nobody? I mean, it is something that is still being worked out, and it’s not entirely clear, but it can happen to someone after they deliver and after they go home. Now let’s say someone has high blood pressure in any of these circumstances, right? You said it’s going to go away, right? So, when is it going to go away? Someone has high blood pressure labor/delivery/right after they deliver and it’s high, how long is it going to last for them?

Dr. Do: That’s a great question, because it lasts for different amounts of time for different people. Sometimes it goes away in a few days, as those hormones wash out. Sometimes it goes away, kind of, not until six to eight weeks postpartum. It takes a while to resolve. And if they’ve had it before pregnancy or, kind of, diagnosed the first half of pregnancy, it might never go away.

Dr. Fox: Right. Yeah, I tell people it’s going to go away somewhere between two minutes and two months after you deliver. And that’s a wide range. Some people literally deliver, their blood pressure is normal, it never goes up again and they don’t need any medicine. They just go home and they’re fine. Other people, it lingers days, weeks, months. If it lasts more than a couple months, we typically think of it as you don’t actually have pregnancy-related hypertension or gestational, you probably have real hypertension because it shouldn’t last more than two months physiologically from pregnancy, because all the hormones from pregnancy should be out by then. And that’s a very wide range. And so because of that, we have to monitor their blood pressure in some capacity for several weeks, at least after they deliver. And how do we do that? What happens? Someone has high blood pressure and they’re going home.

Dr. Do: Everyone who’s had high blood pressure in labor or delivery or postpartum should go home, checking their blood pressures twice a day at least, and having a sense of what’s normal for them and calling their OB provider if it’s higher than what’s normal for them, kind of, on their blood pressure medication or just off of blood pressure medication. And then we like to see them for an early postpartum visit in the office to have a check in at one to two weeks after they deliver for having a sense of what’s going on. And then even if it does go away at those two months, we know that those are women who have higher risks of having high blood pressure long-term, kind of, maybe a five times increased risk of having long-term hypertension that comes up later in life. And so it can be nice to see a cardiologist and, kind of, have a doctor who manages high blood pressure long-term to check in and know about them.

Dr. Fox: Yeah, and that again is a very wide range. I mean, like you said, anyone who goes home with high blood pressure, they need to be watched very closely. And that could mean them checking their blood pressure at home themselves. That’s fine, obviously. And some of them are on medicine. Some of them are not on medicine. It sort of depends how severe the blood pressure is. And then with time, again, days, weeks, months, that blood pressure should just naturally start to improve. Either it’ll go away or if they’re on medicine, you can, sort of, lower their dose until they’re off completely and then be done. And so, again, for almost everyone, by the time six weeks, two months hits, they’re totally fine. Blood pressure is normal. They’re off medication. Again, if they’re still on it, they probably have real hypertension but almost everyone else, it’s gone. But like you said, it’s gone but now they’re in a new class of risk. So, let’s talk about that. So, someone has high blood pressure at the end of pregnancy. Why on earth would that put them at risk for high blood pressure later in life? Is it that the high blood pressure pregnancy changes their body and puts them at risk or is it just unmasking something about them like a risk factor?

Dr. Do: Ongoing research on which of the two it is, I feel like pregnancy is a stress test for moms and so it can unmask things certainly that they have a predisposition to and might come up later in life when there’s more stress that accumulates. It also might be stress on the body itself, these things.

Dr. Fox: Right, it could be both.

Dr. Do: It could be both.

Dr. Fox: It could be both. It’s definitely a stress… And we see there’s a similar concept like with diabetes or pregnancy. Women who get diabetes and pregnancy, same thing. It goes away after delivery and we check them. It’s not quite as critical as the blood pressure. They don’t to check it every day, typically. But a month later, two months later, they repeat the diabetes screen. And even if it’s totally normal and we’re confident everything is gone, we tell them you’re at increased risk of getting diabetes 5, 10, 20 years from now. And they’re like, “Why?” We say, “We’re not really sure. It could be that you were just always at high risk and pregnancy unmasked it for whatever reason, or somehow it changed your body in a way.” I think for diabetes, it’s probably more the unmasking. But hypertension, it could because it could affect your blood vessels. It could affect, sort of, the inner lining and all these things. It’s definitely possible to be either. But it’s a real thing. And so you mentioned seeing a cardiologist. What else can people do when they have this information?

Dr. Do: Yeah. One is healthy diet and exercise, because that’s going to decrease their long-term risk of high blood pressure and heart disease that goes up also after having pregnancy-related hypertension. They should let their primary care doctor know so they can get followed regularly with their primary care doctor.

Dr. Fox: Yeah, I think that’s probably the biggest one that I try to always remind people with diabetes or pregnancy, with high blood pressure and pregnancy, hemorrhage, whatever it is, I say like when you’re pregnant, it’s part of your medical history. We think of it as, sort of, like this silo that everything that happens in… Like Vegas, what happens in pregnancy stays in pregnancy, but it’s not really true. And so when people are seeing their primary care doctor, internist, family doctor, whoever it is, tell them, “Hey, when I was pregnant, I had high blood pressure around delivery. I was on a blood pressure medicine for two weeks and then it got better.” And if you’re seeing a good doctor, they’ll know, “Okay, this is someone who has an increased risk of hypertension.” No different than if you told them my mother has hypertension, my father has hypertension, my sister has hypertension. They’re going to think of you differently than if you said I have no family history of hypertension appropriately because you’re at an increased risk. And these are things that, again, good doctors will know to ask you about or if they didn’t ask you and you tell them, they’re going to know what the implications are. And on the patient end, help them. Tell them, “Hey, this is what happened to me in pregnancy. Look, write that down, put that in my file.” And that’s really important. I think that’s something that doesn’t happen a lot certainly in this country. I think most people have no idea what happened to their patients during pregnancy.

Dr. Do: And there’s so much going on in the early newborn postpartum period. So, once you’re past that, kind of, frequent check your blood pressure as things have resolved and gotten back to normal, it’s not urgent that you see your primary care doctor. There’s a lot to care with baby breastfeeding and all the joyful but hard things early, but in the next year or so, good to see your primary care doctor.

Dr. Fox: I mean, it’s always good to maintain a healthy diet and to exercise. For some people, this is a little reminder like, “Hey, you really got to do this.” I mean, everyone should do it, obviously. But this can be sometimes like an impetus for people to say, “Hey, I got to…” whatever it is, “I got to stop smoking, I got to whatever, lose some weight, I got to get on the treadmill, whatever, all the things we all try to do to stay healthy.” Now, what about… So, this has happened. They recovered, they’re fine. Everything’s good. They told their primary care doctor. They’re A plus. They’ve done everything. Now they’re going to get pregnant again. How do you counsel them about what may or may not happen in the next pregnancy?

Dr. Do: When you’ve had it in one pregnancy in general, for many things, preterm birth, diabetes, high blood pressure pregnancy, there’s an increased risk of having it in your next pregnancy. So, you’ll tell your OB and your OB will check some baseline labs in the early part of pregnancy for, kind of, looking at, kind of, how things are going early on and look at blood pressures in early pregnancy and then start a low-dose aspirin. And why do we start low-dose aspirin? We think that helps decrease the risk of having the high blood pressure syndrome later on in pregnancy because it works on the placental uterine connections to help have better blood flow to the placenta, decrease risk of placenta sending out the stress signals that can cause preeclampsia.

Dr. Fox: So, when you said that someone’s at an increased risk, if someone wanted you to quantify that for them to like, “Well, how high of a risk? How high are we talking about?” So, how would you answer that?

Dr. Do: Part of it depends on how severe it was when they got it in pregnancy and do they have underlying high blood pressure outside of pregnancy. So, if it’s, kind of, mild, that happens just around labor and delivery, full term, probably in the 10% to 15% risk versus if they have underlying high blood pressure, it was severe. It happened early on in pregnancy, 25% to 50% risk.

Dr. Fox: Yeah. And it could be high. The low-dose aspirin does seem to lower it a bit. We also follow them closely in pregnancy. I’ll frequently have them actually check their blood pressure every day at home when they’re pregnant, because like we said, you won’t know if your blood pressure is going up by symptoms. Typically, most people don’t have symptoms. Now, we do check blood pressure at every prenatal visit. But from 24 to 32 weeks, that’s a 3-month time period. You may have three visits and that’s it. I don’t know. I’m a fan of people checking their blood pressure at home when they’ve had a history of high blood pressure in pregnancy. I don’t know if that’s universally accepted, but that’s what I like to do. And I just think it also gives people the reassurance that their blood pressure is normal. Check when you wake up. It’s normal. Go about your day and everything is fine.

But again, these are things that are evolving, especially now that it’s so much easier for the people to check their blood pressure because you can get automated cuffs, which some aren’t so great but some are really good. And there’s all these other systems now to, sort of, get that information, sort of, directly imported into your doctor’s chart, into that electronic medical record. And there’s all these systems and devices that have been developed, are being developed, and, sort of, being piloted and a lot of different high-risk patients. So, I think that’s something that’s going to continue to evolve with time, people doing things from home rather than they need to come to the doctor’s office. COVID definitely turbo boosted this, but I think that that’s continuing.

Dr. Do: And the low-dose aspirin is really reassuring for no increased risks to moms or babies from the pregnancy, from what we’ve seen in tens of thousands of women it’s been studied in. And maybe for that severe early onset, kind of, scary, kind of, high blood pressure pregnancy, it’s the most effective at about 40%, decreasing the risk of that. So, kind of, we’re not worried about long-term implications for moms and babies for the pregnancy when it’s later and happens more subtly.

Dr. Fox: Absolutely. All right. I think we covered the whole thing. So, hypertension, it’s not to be trifled with. Serious stuff.

Dr. Do: Yeah. Lots of close monitoring. Good outcomes expected with lots of close monitoring.

Dr. Fox: Thank you, Dr. Do. Thanks for coming on and talking about a really important topic.

Dr. Do: Thanks, Dr. Fox, for having me.

Dr. Fox: Thank you for listening to the “Healthful Woman” podcast. To learn more about our podcast, please visit our website at www.healthfulwoman.com. If you have any questions about this podcast or any other topic you would like us to address, please feel free to email us at hw@healthfulwoman.com. Have a great day.

The information discussed in “Healthful Woman” is intended for educational uses only. It does not replace medical care from your physician. “Healthful Woman” is meant to expand your knowledge of women’s health and does not replace ongoing care from your regular physician or gynecologist. We encourage you to speak with your doctor about specific diagnoses and treatment options for an effective treatment plan.