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Episode 41: Due Dates are ESTIMATED

birth prep intervention pregnancy May 09, 2022

We're talking about due dates and the fact that they are estimated! Let's call them due months. This is an important topic because surveys have found that up to 40% of pregnant people experience their medical care provider discussing medical induction with them because they are are near or at their due date. That means having an accurate understanding of due dates is essential if 40% of you are going to be grappling with whether or not to have a medical induction based on your due date! 

In this video we discuss:

  • Why understanding due dates is important.
  • How due dates are determined (last menstrual period and via ultrasound, and weaknesses with each method).
  • A brief discussion on why medical inductions are offered later in pregnancy. 

 As always, I'm wishing you the best on your brave journey through pregnancy and preparing for birth! See you next week.

Full Transcript:

[00:00:00] Hello, and welcome back to your next free weekly Brave Journey birth preparation video, where I pick a topic related to birth or postpartum and I talk about it. Today we're talking about due dates and the fact that they are estimated. Let's call them due .Months. I don't want to hear people calling them due dates anymore. They are estimated. I'm Cara Lee. I'm a birth doula and childbirth educator, and let's get started.

So why are we talking about due dates today? The reason is because in 2017, a bunch of birthing people were sampled and over 40% said that their medical care provider talked to them about induction due to being near or at their due date. So that means that a huge percentage of people are navigating [00:01:00] whether or not to have a medical induction as they near their due date. And so this means that the due date has a lot of importance.

Now the benefits and risks of a medical induction and the medical induction process is another topic for a different video. We have lessons on this in the Brave Journey Birth Preparation Program, about the benefits and risks of induction, as well as tips for how to have a successful induction.

We've also talked about this in the past, in prior weekly videos. So you can go click on those, but what we're talking about today is due dates. And since so many people end up having to grapple with whether or not to have a medical induction due to coming to their due date or passing their due dates, I wanted to talk about this today.

First off, let's talk about how do we even get to a due date. And the big thing to emphasize here is that is always estimated. There's going to be a range of when every human body gives birth to a baby. And there's going to be a range of when every human body who menstruates, in terms of when they ovulate, and when they conceive.[00:02:00]

So if you are calculating your due date by your last menstrual period LMP, then that means that your medical care provider has assumed that you have a 28 day cycle. Now, do you have a 28 day cycle? No, none of us do. Well, maybe you do people range from 25, 26 day cycle to 30, 35 day cycle.

So if you have a 31 day cycle, that's three days past 28 days so you probably ovulated three days later. So your estimated due date based on a 28 day cycle, it means that your due date is established three days earlier than actual. So your medical care provider may say on 40 weeks, exactly, we're starting a, an induction process and then that's actually 39 weeks and four days for you. So this is an example of how it's estimated. And maybe, you know exactly when you ovulated . So you can share that with your medical care provider when establishing a due date. Estimated due date.

Another way that due dates are established [00:03:00] is from ultrasound. Now, ultrasounds can give you a very accurate due date, only in a very narrow window of gestation between 11 weeks gestation and 14 weeks gestation. At that point an ultrasound is as accurate or more accurate than knowing when you ovulated or last menstrual period.

However, if your first ultrasound is prior to 11 weeks gestation, Or after 14 weeks gestation, it is becomes less and less accurate. If it's after 20 weeks gestation, it is not accurate. So it is not, it's going to give you an idea of broadly of how many months pregnant you are, but it's not going to give you this exact estimated due date.

Now medical care providers have to do the best they can. They put it in the system, but then when you get to the end of your pregnancy, if you're not totally sure about your, due date, you're facing all sorts of decisions based on an estimated due date. And they're to the day.

So I want to say again, ultrasounds later in your pregnancy, you know, when you go in for ultrasounds at the end of your pregnancy, and somebody says, "oh, [00:04:00] she's measuring earlier". "Oh, they're measuring late". Um, that's not accurate, so don't let it get in your head. I've seen so many people get it in their head when their ultrasound tech is like, "oh, you're measuring a few days early".

And they're like, "oh, this baby's going to be born a few days early."

Not necessarily, it is not that accurate. So late ultrasounds can tell you a lot of interesting and important things about your infant and your pregnancy, but they cannot give you a good idea of when your baby will be born or an more accurate due date.

Sometimes they'll want to change your due date if it's later on in your pregnancy and you're getting some different information and it's not a good time to do that.

Finally, now 40 weeks gestation is what is assumed to be the average human gestation. But when you look at actual data and analyze when people, first time, birthing people actually spontaneously go into to labor. Only half of all birthing people will spontaneously have started labor by 40 weeks and one day. So if you are looking at starting at 38 weeks, you're like "any day now, any day now", [00:05:00] and at your 40 weeks you're like, "oh, I'm late. This baby is late". This is not true. Only half of people will spontaneously go into labor by 40 weeks. That means half of us, half of you will not spontaneously start labor before 40 weeks.

Now 75% of people will have spontaneously started labor by 41 weeks. And let me look by 41 weeks and two days. So 75% of first-time birthing people will have spontaneously started labor by 41 weeks. And 2 days. So what that means is 25% of first-time birthing people will not have spontaneously started labor by 41 weeks and two days.

If your medical care provider is one that recommends induction at 41 weeks, then 25% of you are going to be talking about induction with that medical care provider and whether or not to consent to a medical induction.

Now reasons for medical induction for estimated due dates going past 41 weeks. After 41 weeks your risk of a stillbirth, and that's [00:06:00] scary, right? Your risk of stillbirth begins to become marginally more possible (meant to say 'likely'). After 42 weeks, the risk of stillbirth starts to go up a lot more. So the American College of Obstetricians and Gynecologists recommends that an induction be performed, that than a baby be born by 42 weeks. That's the recommendation, but it can be considered as early as 41 weeks. So that's the official recommendation. For those specific details and those specific data, you can reach out to me if you'd like to look at those, those are available also at Evidence Based Birth.. And I have some handouts on some of those statistics.

They're scary. And that's why these conversations can be tricky to have with your medical care provider, when they say things like "stillbirth", our minds tend to go blank. But we have to really look- eyes wide, open- at actual risk and understand that when it goes up just a tiny little bit versus goes up a lot.

We are the only ones who can make that decision for ourselves. It also has to do with our goals, for what kind of labor we'd like to have and our perceptions on medicine and [00:07:00] risk. So each of us has a different way of approaching that and every medical care provider has a different way of approaching that, too.

So your personality and your perceptions on medicine and risk and your medical care provider's perceptions on medicine and risk will come to play here.

One last final note, there was a study that came out that showed a higher risk of cersarean birth after 39 weeks. So. A lot of medical care providers have started to offer elective induction at 39 weeks.

Again, we haven't talked about benefits and risks of induction. We're just talking about due dates, but I do want to mention here that there are a lot of things that will more significantly reduce your risk of cesarean and birth than an induction at 39 weeks. Things like having a birth doula can decrease your risk of giving birth via cesarean by something like 37%.

So there are a lot of different things that you can do to reduce your risk of a cesarean section, aside from induction at 39 weeks, because induction does, becomes a medicalized process.

Okay. So the primary points for this due dates topic, is that due dates are estimated, due [00:08:00] dates are estimated, due dates are estimated.

We should really be talking about a due month. You should really be thinking my baby will be born at any time between 37 weeks and 42 weeks. That's a five week window. You are not overdue after 40 weeks. Only 50% of people will have spontaneously started labor by 40 weeks and only 75% by 41 weeks. So expect your labor (meant to say "pregnancy"!) to go long. You can be ready. Have your labor bags packed at 37 weeks, but don't expect to go into labor until 41 weeks, and you can be excited if you're just one of those people- or horrified, depending on your situation- if you're one of those people who goes into labor early. So that's it for Due Dates are Estimated and, I will see you in the next video.



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