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"G" is for "Guess Date"

Well, it's been a second since our last ABC post, but we finally made it to "G", and this is a very relevant topic for our pregnant mamas!


If you've ever been pregnant, you know that one of the first things your OB/GYN or midwife will discuss is your "due date", or as we like to call it, the "guess day". Some providers will feel strongly about this, while others may feel a bit more flexible. There are also standards that vary from state to state, and hospital to hospital!


But first, a little history lesson (feel free to scroll past this if you're bored):


"In 1744, a professor from the Netherlands named Hermann Boerhaave explained how to calculate an estimated due date. Based on the records of 100 pregnant women, Boerhaave figured out the estimated due date by adding 7 days to the last period, and then adding nine months (Baskett & Nagele, 2000).

However, Boerhaave never explained whether you should add 7 days to the first day of the last period, or to the last day of the last period.

In 1812, a professor from Germany named Carl Naegele quoted Professor Boerhaave, and added some of his own thoughts. (This is how Naegele’s rule got its name!) However, Naegele, like Boerhaave, did not say when you should start counting—from the beginning of the last period, or the last day of the last period. His text can be interpreted one of two ways: either you add 7 days to the first day of the last period, or you add 7 days to the last day of the last period.

As the 1800s went on, different doctors interpreted Naegele’s rule in different ways. Most added 7 days to the last day of the last period.

However, by the 1900s, for some unknown reason, American textbooks adopted a form of Naegele’s rule that added 7 days to the first day of the last period (Baskett & Nagele, 2000)."-Evidence Based Birth


So what does this mean? Well, it means that your provider is probably making decisions on a metric that is more of a guideline than a fixed point. This current model of calculation assumes that all women have a 28 day cycle (many don't) and that you ovulate on day 14 (many don't). It also assumes that all babies come out exactly at 40 weeks, when in reality, the stats show anywhere from 38-42 weeks is "normal", with first time mothers often leaning towards the later dates.

Now, this doesn't mean that specific dates are useless! Medical professionals obviously need to have a general idea of baby's gestational age so they can track progress and trouble spot things if they come up. The issue can be when a specific date is used to manipulate the patient into *unnecessary* interventions or even surgery. There are of course many situations where doctors need to act within a certain time frame, but there are plenty of situations where baby is just not ready to come out...and that requires patience.



-About 10% of the 3.8 million babies born in the United States in 2017 came preterm (before 37 weeks).

-26% were born in weeks 37 to 38

-57% in weeks 39 to 40

-6% in week 41

-Less than 1 percent at 42 weeks or beyond."


It also doesn't mean that you should entirely ignore where you're at in pregnancy and the *potential* complications. Some providers may have you "risk out" past a certain week (homebirth midwives especially) and many will want to keep a closer eye on things as you go past the 40 week mark (and beyond). Be prepared for more frequent labs, or additional stress tests, but know that you still have the right to ask questions and yes, even decline interventions and tests. Do your research and find your own informed comfort zone. One of our purposes as doulas is to facilitate education and growth, so that our clients feel equipped to ask their own questions and make their decisions. We aren't the ones growing, birthing and feeding babies. We aren't creating your new family unit. When we present information like this, our goal is not to coerce or sway your decision making process. It's simply meant to give you all the information available, so you can figure out what works for you! And whatever you choose, we will have your back. :)


In our humble opinion, viewing your due date as something set in stone is not the most helpful approach. Instead, try viewing it as a general timeframe. The end of pregnancy is just as much a mental game as it is a physical game. Set yourself up for success by preparing for those last few days and weeks with fun distractions, lots of REST, and claiming every day as a "bonus day", both for baby and yourself! Look up all the amazing ways baby is growing and preparing for the outside world. Soak up the moments with just you and your spouse, or the last few evenings as a family of 3 (or 4, 5, 6, etc). Finish the organizing, get ahead on work projects, and again, REST.

You will eventually make it to the finish line, we promise! Pregnancy and birth, much like due dates, are as unpredictable as parenting is. So maybe take those last few weeks as preparation for your next few years, 😉


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