00:00:00 – Dr. Rebecca Dekker
Hi everyone. On today’s podcast, I’m going to do a mini Q&A on early induction for gestational hypertension, the newest research on acupressure and acupuncture for labor and birth, and the impact of spacing your pregnancies on birth outcomes.
Welcome to the Evidence Based Birth® Podcast. My name is Rebecca Decker and I’m a nurse with my PhD and the founder of Evidence Based Birth®. Join me each week as we work together to get evidence-based information into the hands of families and professionals around the world. As a reminder, this information is not medical advice. See ebbirth.com disclaimer for more details.
00:00:44
Hi everyone, and welcome to today’s episode of the Evidence Based Birth®Podcast. Today, I’m so excited to answer some questions that we’ve been answering this year inside the Ask the Research Team Forum just for EBB Pro Members. So if you’ve ever wanted to personally ask me or the other researchers at Team EBB a question, you can do so inside the EBB Pro Membership, and you can learn how to join at ebbirth.com/membership. We do have monthly, quarterly and annual membership options available, as well as scholarships.
00:01:15
Today, I’ve chosen three questions and answers to share with you publicly on the podcast, and they have to do with the timing of a scheduled induction for gestational hypertension, new research on acupuncture and acupressure for labor and birth, and the impact of spacing of pregnancies on pregnancy and birth outcomes. One more announcement I wanted to make before we get started that is related to the subject. We are hosting a training all about evidence-based care for gestational hypertension and preeclampsia on June 4th. This training will be led by Dr. Shannon Voogt, a board-certified family medicine physician, and it’s a fantastic training opportunity for doulas, nurses, midwives, and physicians to stay up to date on what kind of care is considered evidence-based for families who are experiencing high blood pressure during pregnancy. And with that, let’s get on to our Q and A.
Our first question today comes from an EBB Pro Member whose childbirth education student is wondering if there’s any data on induction time periods and corresponding outcomes.
00:02:17
They realize that most randomized trials on scheduling an induction are generally looking at induction at 39 to 41 weeks and as opposed to spontaneous birth. But what this family is likely going to experience is an early induction at 37 or 38 weeks due to gestational hypertension. And this family was asking their childbirth educator if there’s any evidence on early induction and how it might impact various birth complication rates, such as Cesareans and NICU admissions.
00:02:47
Our Research Fellow at EBB, Dr. Morgan Richardson-Cayama, put together some research for me to share with this EBB Pro Member. Now, when it comes to 39 and 40 week inductions, we talk about that in our recently published Signature Article on the ARRIVE trial and elective induction at 39 weeks, which you can access at https://ebbirth.com/ARRIVE. This family is correct in noting that much of the research on scheduled inductions has been around the 39-week mark.
00:03:17
Many of you listening may already be familiar with our ARRIVE Trial article and the research on 39-week inductions, which we’ve already talked about in depth on this podcast. I’m not going to go into too much more detail, but basically, the research is still mixed on whether 39-week elective inductions lower Cesarean rates, and there’s also mixed evidence on whether 39-week inductions lead to lower or higher rates of post-birth complications for babies. Most of the research we have so far does not show clinically significant differences between 39-week induction and expectant management.
00:03:52
While some studies have found higher risks for issues like shoulder dystocia when births are induced, one of the four recent studies we looked at did find that there were higher rates of infants needing immediate assistance with breathing support after the ARRIVE trial came out, and 39-week induction rates went up. But this study includes elective inductions, medically necessary inductions, and expectantly managed births where people went into spontaneous labor. And most of this research on 39-week induction has been with low-risk first-time people giving birth.
00:04:25
So it might not be relevant for this particular family, who’s looking at a diagnosis of gestational hypertension. So let’s look a little bit more closely at the research on induction for gestational hypertension. First of all, the clinical guidelines of the American College of Obstetricians and Gynecologists, or ACOG, recommends early term birth at 37 weeks for those with gestational hypertension without severe range blood pressures, and they recommend late preterm birth at around 34 weeks for those with severe range blood pressures.
00:04:58
In the United Kingdom, the National Institute for Health and Care Excellence (NICE) does not recommend a planned early birth before 37 weeks for those whose blood pressure is lower than 160/110 unless there are other medical issues. The NICE believes that timing of birth for these people should be determined by shared decision making with the healthcare provider and consideration of any maternal or fetal indications.
So, looking for some recent published research on this topic, we came across a recent randomized controlled trial called the WILL Trial, W-I-L-L, When to Induce Labor to Limit risk in pregnancy hypertension. The goal of this study was to determine the best birth timing for those with chronic or gestational hypertension. This study was done in the United Kingdom, and it’s open access. If you’d like to learn more, I’ll link to it in the show notes. To be included in this study, participants had to have chronic or gestational hypertension, defined as a systolic blood pressure of 140 or greater or a diastolic blood pressure of 90 or greater. They were excluded from the study if they had preeclampsia or severe hypertension or any major fetal health issues, and the primary outcome they were looking at in this trial included severe hypertension, maternal death, or maternal morbidity.
00:06:20
Their primary health outcome for newborns included NICU admission for at least four hours, but they also looked at a range of other health outcomes, including Cesarean birth, the need for interventions, respiratory issues in infants, APGAR scores, rates of sepsis, low birth weight, and more. They included about 400 people in this study. Two hundred were randomly assigned to a planned early term birth at 38 weeks, so this was the intervention group, and 200 were assigned to usual care. The early-term birth group included those who had labor inductions or planned Cesareans.
Overall, they found no differences between the two groups in their primary maternal outcomes. They did find evidence that more people in the intervention group received postpartum blood transfusions, although the percentages were low overall, 4.5% versus 1%. They also did not see any significant differences in Cesarean rates or in infant health outcomes, including breathing problems. It’s important to note that 70% of the participants who are assigned to the usual care group, who were supposed to go until term to deliver, still ended up having their labor induced based on clinical need. So those in the early induction group or the intervention group had an average timing of giving birth at around 38 weeks, and those in the usual care group gave birth at around 39 weeks. So we’re really only looking at a difference of about one week in the timing of giving birth.
00:07:48
Another study looked at data collected during another randomized trial that was looking at hypertension in pregnancy. So they were kind of doing a secondary data analysis and looking a little bit more into the data that was collected in this study. They were particularly interested in a maternal composite outcome, which means they combine a bunch of different things, and if you have one, you’re considered to have a bad maternal health outcome. This included death, serious illness, ICU admission, preeclampsia, hemorrhage, among a few other things.
00:08:23
They also had a combined neonatal outcome. Serious outcomes that could be included in this included death, the need for respiratory support, low APGAR scores, seizures, or sepsis. They also collected data on Cesarean rates, NICU admission rates and respiratory distress syndrome. This study included 1,417 participants. About 22% of them had a new diagnosis of gestational hypertension, and the other 79% had known pre-existing chronic hypertension. The researchers compared outcomes between those who had planned deliveries and those who had expectant management, and they looked at different weeks of gestation at 37, 38, and 39 weeks. They found no differences between the groups in the primary maternal or newborn composite outcomes for any of the weeks.
However, they did see higher rates of respiratory distress syndrome at 37 weeks in those with planned deliveries versus expectant management at 37 weeks, and they had higher rates of low blood sugar in babies at 37 and 38 weeks in those who had planned deliveries at those times versus expectant management. In terms of the health risks for a baby who’s born at 37 or 38 weeks versus waiting a little bit longer, we do know that risks of health issues are higher the earlier a baby is born before 39 weeks.
00:09:47
These kinds of health problems can include respiratory problems, developmental delays, and longer-term health issues like neurological disorders. However, you have to balance that against the risks of continuing a pregnancy for those with gestational hypertension. The risks that can go on the longer you’re pregnant with high blood pressure include the development of preeclampsia, kidney failure, fetal growth restriction, placental abruption, and low birth weight.
00:10:15
If a family is not sure what they want to do, or they’re thinking about advocating for an induction beyond that 37 or 38 week mark. It seems that the risk versus benefit equation may really depend on the severity of the hypertension in that person’s situation and any other maternal or fetal risk factors. Ideally, a family would be with a provider that they feel comfortable talking about all of these issues with, and there would be shared decision-making and an open conversation about the risks and benefits of different options.
00:10:47
So I hope this info is helpful, and we’re thankful to our Pro Member for asking such an interesting question. We’ll link to these studies and a few other resources about high blood pressure and pregnancy in the show notes. Our next question came from an EBB Instructor who is also a Pro Member.
00:11:03
They said that their Childbirth Class student from the Evidence Based Birth® Childbirth Class would like some updated evidence on acupuncture and acupressure for labor and birth. They felt like they wanted some more updated or recent info or studies that have come out since we last published materials on acupuncture and acupressure and Evidence Based Birth®. So, Sara Ailshire, our Research Fellow here at EBB, put together a short review of some of the research on acupuncture and acupressure that has come out since we last published on this topic in 2020. There was a systematic review published in 2021 investigating the effectiveness of acupuncture and moxibustion on getting babies out of the breech position. The reviewers looked at 16 randomized control trials that enrolled a total of 2,555 participants. They found that the research is still not clear whether or not acupuncture has an effect on turning breech babies.
00:12:01
However, they did find that moxibustion seems to have a positive impact on turning breech babies. There’s also a 2021 Cochrane review published looking at interventions to prevent nausea and vomiting after a Cesarean, and they found that acupressure might lower the risk of vomiting during a Cesarean, but research remains inconclusive as to whether or not it prevents vomiting or nausea post-birth with a Cesarean.
00:12:41
A 2021 study from Iran compared the effect of acupressure with or without ice on the Large Intestine 4 point or LI4 point on labor pain and anxiety. In this study, 90 women were randomized into three groups. 30 women received acupressure with ice on LI4, 30 received acupressure only on LI4, and 30 received no acupressure and served as the control. Women in both the acupressure-only group and the acupressure and ice group reported decreases in labor pain after the treatment, with the acupressure-only group reporting a slightly larger decrease in pain than the acupressure with ice group. They did not find any statistically significant differences in anxiety between the three groups.
00:13:12
A 2022 study also from Iran, looked at how acupressure and supportive care from a doula during labor can help reduce maternal anxiety compared to typical hospital care. In this study with 150 laboring women, 50 were assigned a doula to help them during birth, 50 received acupressure at the point Bladder 32, and 50 received no intervention and served as the control group. The researchers found that birthing women in the doula group and the acupressure group both reported less anxiety than women in the control group.
00:13:52
The researchers also looked to see if there was any impact of these supportive measures on oxygen levels in the umbilical cord. The researchers found that oxygenation, which they measured as oxygen pressure or PO2, was higher in the umbilical cords of babies whose mothers received acupressure or doula care compared to the control group.
00:14:12
There was also an interesting randomized control trial published in 2022 that looked at the effectiveness of acupuncture for pain management after an elective scheduled Cesarean, comparing it to placebo treatment as well as comparing it to a control group. In this study, 60 women received acupuncture, 60 received a placebo or sham or fake acupuncture, and 60 received standard post-Cesarean birth care. Participants in both the acupuncture and the placebo acupuncture groups reported less postoperative pain.
00:14:46
Both the acupuncture group and the placebo acupuncture group required less opioids for pain management compared to the standard care group, with 12% of the acupuncture group and 10% of the placebo acupuncture group requiring rescue opioid treatment for pain compared to 20% of the standard care group. Women who received acupuncture were more likely to be mobile the day of their Cesarean (68%), compared to the placebo acupuncture group (32%), and the standard care group, 20%. The acupuncture group was also more likely to be fully mobile on the first day after their Cesarean (98%), compared to the placebo group (83%), and the standard care group (58%).
00:15:31
Researchers noted that those who received acupuncture during the study did report higher levels of pain while they were moving around on the first day after the Cesarean than they expected. Although these levels were still lower than what were reported by the control group and the placebo group, the researchers hypothesized this might be related to how quickly the acupuncture group returned to full mobility.
00:15:54
And the researchers pointed out that recovery after Cesarean might not be centered just on pain relief alone, but also on mobilization and getting more quickly back to being able to move around.
There was also an interesting article published in 2022 that explains from the perspective of practitioners of Chinese medicine based in Taiwan, all about how acupuncture works and its impact on a variety of pain conditions, including how it might impact labor and childbirth.
00:16:23
I’ll also link in the show notes to an article published by Harvard Medical School that you might find interesting.
So in this little Q and A, I was focusing on the newest research on the subject, but I also want to share EBB’s prior work on acupuncture and acupressure. We have published episodes on this in 2020 and also in 2018, and we’ll link to those in the show notes as well.
Our final question from today comes from an EBB Pro Member and Instructor who had a specific question about the research on stillbirth risk.
00:16:54
So, as a quick content note, we will be discussing statistics on stillbirth in this final section of today’s episode. Their question is if someone is 40 years old and expecting their second baby and their first pregnancy and birth went well, then according to the research that we highlighted in the Evidence Based Birth® Signature Article on Advanced Maternal Age, this person would theoretically be grouped with other people who’ve had a prior live birth. And if you’re advanced maternal age but you’ve had a prior birth that went well, then this significantly lowers the risk of stillbirth to actually be lower than someone who is younger than 35 and having their first baby.
00:17:35
But what if this same person has had more than five years since their last birth? Then would they technically be categorized as not having had a baby before? And would their stillbirth risk be more in line with someone of advanced maternal age who’s having their first baby? Also, the person asking this question is wondering if they’re more likely to have a longer or a very long labor because it’s been such a long time since having their first baby.
00:18:02
So they really wanted to know what is the evidence on the risk of poor birth outcomes and longer labors if you have a longer spacing between births? So this is a great question, and I’m the one who dug into the research on this subject for this member.
So I did a search on PubMed and I found a few articles from a while ago. The keywords that I used in my search were interdelivery interval and pregnancy interval.
You might be wondering, like, what do these terms mean? Interdelivery interval and pregnancy or interpregnancy interval? So, part of the problem I ran into when summarizing this research is that every group of researchers seems to define it slightly differently, so it makes it really hard to combine research results. Interdelivery interval usually refers to the time interval from one birth to the next birth. A pregnancy interval usually refers to the interval from the beginning of one pregnancy to the beginning of the next. And you can also see some people referring to pregnancy spacing as being the space between the time you gave birth to one child and the time you got pregnant with the next.
00:19:10
Now in general, researchers use interdelivery or interpregnancy intervals, which are roughly the same with the problem of preterm births because a preterm birth would shorten the length of an interdelivery interval. Anyways, these terms can all get quite confusing. So what I’m going to do is focus on the research on interdelivery intervals in general because I could not find studies specifically focused on advanced maternal age and interdelivery intervals.
00:19:39
This person was really interested in pregnancies at the age of 40 and older, and I couldn’t really find anything on that, and pregnancy spacing. One of the studies I found was published in 2016, and it was a study of 1.9 million births in the US, and it was carried out between the years 2011 and 2012. This group of researchers found that both shorter and longer interdelivery intervals were associated with worse birth outcomes. A short interdelivery interval was defined by this group as less than 17 months between births. Short interdelivery intervals were associated with higher rates of preterm birth, higher rates of low 5-minute Apgar scores, small for gestational age, and NICU admission. Meanwhile, a long interdelivery interval, which they defined as greater than 60 months, was associated with higher rates of labor induction, higher rates of Cesarean, infection, maternal ICU admission, preterm birth, small for gestational age, low 5-minute Apgar scores, and NICU admissions. So that study was done in the US, a large population-based study. I found another study published in 2020 that was focused on interdelivery intervals in low- and low-middle-income countries. They included more than 180,000 women from healthcare sites in the Democratic Republic of the Congo, Zambia, Kenya, Guatemala, India, and Pakistan.
00:21:03
One of the reasons I looked at this study is that they examined rates of obstructed labor. So obstructed labor is a very long labor that can be quite dangerous in a developing nation when you don’t have easy access to operating rooms or Cesareans. They found higher rates of poor outcomes, including higher rates of obstructed labor, with both the short and the long interdelivery intervals. They defined a short interdelivery interval as 6 to 17 months and a long one as 61 to 180 months. And their reference or normal group was defined as 18 to 36 months between deliveries. In comparison to their normal or reference group, the group with very short interdelivery intervals had a higher risk of newborn death, stillbirth, low birth weight and very low birth weight.
00:21:52
The people with long interdelivery intervals had an increased risk of maternal death, newborn death, stillbirth, low birth weight, and very low birth weight. Both short and long interdelivery intervals were associated with an increased risk of having an obstructed labor which, as I said earlier, can be very dangerous in some countries and lead to higher rates of maternal mortality. The absolute risk of obstructed labor with a very long interpregnancy interval of 61 to 180 months was 4.5%, compared to 3.1% in the group with the normal interpregnancy interval of 18 to 36 months and 4.1% in the short interdelivery interval group.
Researchers in Canada looked at 46,000 patients who gave birth in the Province of Alberta between 1999 and 2007. They defined a short interpregnancy interval as 0 to 5 months or 6 to 11 months and a long interpregnancy interval of 36 months or longer. You might be wondering how can you get your pregnancy space so shortly together? Well, if the first one ended in a miscarriage and then you got pregnant quickly after, that would be considered a pretty short interpregnancy interval.
00:23:03
These researchers found higher rates of poor outcomes in both the short and the long groups. Specifically, they found an increased risk of low birth weight and small for gestational age with both the short and the long interpregnancy intervals and an increased risk of stillbirth and newborn death with long interpregnancy intervals.
00:23:22
Then what might be most helpful of all? In 2023, researchers performed a meta-analysis where they combined interval health outcomes from studies from around the world. They included 129 studies with more than 46 million pregnancies. They defined the reference or the ideal interpregnancy interval and as being between 18 to 23 months. And compared to that ideal or reference, they found that the shortest interpregnancy interval of less than six months and the longest interval of greater than 160 months had the highest rate of poor health outcomes including preterm birth, small for gestational age and stillbirth.
Now, I know this research might have seemed scary, so I want to give you a couple of my thoughts after reading through this research. First of all, correlation does not mean causation. It could be that people with long interpregnancy intervals who had adverse health outcomes had that long interpregnancy interval because of some health condition or poor nutritional status, or maybe due to fertility struggles, indicating possible underlying health conditions.
00:24:30
So it might not mean that the long interval caused the poor health outcome, but maybe there is something else going on, an underlying health condition that led to the long interval, and so it’s that underlying condition that may have led to the adverse health outcome. Second of all, stillbirths are a rare outcome and these studies are mainly reporting relative risk, not absolute risk. So I can’t share the actual statistics with you on what are the actual chances of someone experiencing a stillbirth. This makes it harder to use these data in risk counseling. Third, as I mentioned earlier, I couldn’t find any papers that sorted this data by maternal age. So I don’t know if there’s any interaction between older age and longer interpregnancy intervals.
Interpregnancy or interdelivery intervals are difficult to counsel people about when they’re already pregnant with that second child, because it’s not always something you can control. Some people do try to time their pregnancies using strategic stopping of birth control, but that doesn’t mean that people get pregnant when they want to or when they plan to.
00:25:38
Also, a significant portion of pregnancies are unplanned. So once someone is already pregnant, that interpregnancy interval or interdelivery interval is already something that’s going to be established. It’s not something you can actively change. So it’s what we call a non-modifiable risk factor. If someone is pregnant and they’ve had a shorter or a longer interpregnancy interval and they’re otherwise healthy, the absolute risks of some of these poor health outcomes would be lower.
00:26:06
At the same time, I could see why some OBs might be concerned about a short or a long interdelivery or interpregnancy interval. And if you have other risk factors for preterm birth or risk factors for stillbirth, such as being 40 or older, I can see why a provider might bring it up when discussing the benefits and risks of planning an elective induction. I also think it’s an interesting global topic and I have seen some people, such as I remember reading Melinda French Gate’s book all about her efforts in helping maternal health at the global stage. And that was one of her key projects for a while, is teaching women around the world about pregnancy spacing.
00:26:49
In general, I think a lot of the public health interventions have been focused on preventing short interpregnancy intervals as a way to optimize health outcomes for both birthing people and babies. So it’s really interesting to look at it from the perspective of how might a long interpregnancy interval affect your health outcomes. Again, we don’t know if this is just a correlation or if there’s some kind of causation going on.
00:27:13
My guess is that more has to do with underlying health conditions that lead to longer intervals between births. These were really thought-provoking questions and this wraps up our mini Q&A all about gestational hypertension and induction, acupressure and acupuncture, and the impact of spacing pregnancies on birth outcomes. Thanks for listening and if you ever have a question about the research, remember that our research team is available to answer your questions inside the EBB Pro Membership. Thanks again and I’ll see you next week. Bye.
This podcast episode was brought to you by the book Babies Are Not Pizzas: They’re Born Not Delivered. Babies Are Not Pizzas is a memoir that tells the story of how I navigated a broken healthcare system and uncovered how I could still receive evidence-based care. In this book you’ll learn about the history of childbirth and midwiffery, the evidence on a variety of birth topics and how we can prevent preventable trauma in childbirth. Babies Are Not Pizzas is available on Amazon as a Kindle paperback, hardcover and Audible book. Get your copy today and make sure to email me after you read it to let me know your thoughts.
