Why Due Dates are Bullshit

There was once a guy called Herman (see below). Herman lived and worked during the 1700’s - a time when very little was known at all about pregnancy or birth. Herman was a clever chap and decided he could figure out a way of predicting the exact date when someone was going to have their baby. Amazing right?! So, the clever clogs that he was decided the best way to do this was by looking at the records of 100 pregnant people and seeing if he could do some sums and work out if there were any clues as to why and when someone would give birth. After a looking at these 100 records, he deduced that you could work out someone’s due date by taking the last period, adding 7 days and then adding 9 months. How simple! What a trick! Thank goodness this very important discovery was made by looking at many thousands of records and speaking to many thousands of pregnant people about their experiences and then thoroughly testing and investigating the theory before it was put out into the world and…oh. Wait. Hmmm.

Another sticking point is that Herm also casually forgot to mention WHEN you start adding FROM. He never clarified whether you start adding from the first day or the last day of the period. It seems like an important thing to miss out…

Based on the very limited number of people involved in this ‘study’ and the general ambiguity in the adding bit (the bit that apparently gives us that magic due date) you’d think that this theory would have been left to gather dust at the bottom of Herm’s office drawers. But alas, you’d be wrong.

Some years later, another guy called Carl came along. Carl loved Herman’s idea so much he decided to expand on it a little. He LOVED the idea of all this adding and counting malarkey but just like Herm, he didn’t think it was all that important to tell people exactly WHEN to start counting. Nevertheless, Naegele’s rule was born!

So, off this theory went into the world with medical people here and there interpreting it how they fancied. Most decided it was best to add 7 days on to the END of the period to get that magic due date and took great pleasure in dishing this information out to pregnant people far and wide. “You’ll be having your baby on the 10th of February Joan!”, “Betty, see you on the 12th of May!” Naegele’s rule, everybody. A rule. A rigid thing that doesn’t change. Applied to an entire population of people whose bodies and babies and cycles are all different. Okkkaaayyy.

So, this went on pretty much throughout the 1800’s until…some other bright chaps decided, “Hey, scrap that. Just to shake things up, why don’t we now start adding 7 days to the START of the period instead?!” Wonderful. What a brilliant idea. And so it goes, this is the current ‘rule’ that governs due dates throughout the world today and what most inductions and post date interventions are based on.

A ‘rule’ that basically everyone has interpreted just how they fancied based on something good old Herm decided back in the 1700’s when viewing the records of just 100 pregnant people. I mean…sounds legit to me?! (Sarcasm. I’m being Sarcastic).

Bodies, babies, cycles – they’re all very individual things. Due dates are ESTIMATES. At best. When you then consider that only 4% of babies are actually born on their estimated due date, it gives us even more reason to believe that this ‘rule’ does not work for the majority of people. The worry is that people can and are offered a series of interventions based on this outdated rule including induction of labour. Induction and interventions are not the devil – in some cases they are lifesaving and needed however, choices such as these must be made by the pregnant person, and they MUST have all of the information available to them to be able to do this.

Estimated due dates are a great example of why it is a good idea to inform yourself in preparation for birth. When you have all of the information, if you find yourself approaching or surpassing your estimated due date, you can then make an informed decision based on evidence and do what feels right for you. This is your body, your baby and your birth. It is always your choice.

If this is something you would like to learn more about you can find lots of excellent information on https://evidencebasedbirth.com/evidence-on-due-dates/.