by Kira

It’s no surprise that in such a busy, fast paced culture we even have “due dates” for our babies. However unlike work projects, there is no real deadline for babies- they’re babies!

There is a lot of conversation around the accuracy of due dates (are ultrasounds more effective? Is 40 weeks actually the length of a “normal” pregnancy?) but for the most part, “doctors, midwives, and online due date calculators use Naegele’s rule to figure out an estimated due date (EDD). Naegele’s rule assumes that you had a 28-day menstrual cycle, and that you ovulated exactly on the 14th day of your cycle (Note: some health care providers will adjust your due date for longer or shorter menstrual cycles). To calculate your EDD according to Naegele’s rule, you add 7 days to the first day of your last period, and then count forward 9 months (or count backwards 3 months). This is equal to counting forward 280 days from the date of your last period. (an excerpt from Evidence Based Birth- Due Dates)”

Even if you know the exact date that you conceived, there is evidence suggesting that the “due date” is actually 3-5 days after 40 weeks. As you can tell, there is a lot of room for variation using this method.

Only 5% of babies are born on their due dates. That means that 95% of babies are born before or after their due dates. In fact, the average first time baby is born 5 days after their due date.

The majority of parents that I’ve worked with shift into a state of concern when they pass their due date. And it’s with good reason! In our culture, it is incredibly rare to let pregnant people go past 42 weeks. And most people prefer not to be induced if they can avoid it.

So, what do we do about it?

Here’s my proposal:

1)    Call it a “guess date”. Heck, call it a “guess month!” Or, at the very least, an “estimated due date”.

2)    Emotionally prepare to welcome baby ANYTIME between 37-42 weeks. Have your bags packed by 37 weeks (if you’re birthing in the hospital or birth centre), but don’t expect baby to arrive before 42 weeks!

3)    Refer family and friends to the statistics in this post early enough in your pregnancy that they get the idea- babies do not arrive “on time”. A huge part of the pressure is family and friends. Be proactive and let them know about the MONTH that you may be waiting for baby to make their guest appearance.

http://www.ontariomidwives.ca/images/uploads/client-resources/Postdates-Final.pdf