Due Dates

A due date is really just a guess date.

Pregnancy has a wide window of gestation, between 265 - 300 days. Full term is commonly known as 40.0 weeks & how this was determined is quite arbitrary and is simple maths.

265 to 300 days. Subtract 265 from 300 = 35 days. Divide the 35 by two=17.5 days; Add 17.5 to 265= 282.5 days. Divide by 7 days in a week = 40.3+weeks that’s just about how scientific the estimate is.

A woman with a healthy pregnancy should not be considered for induction until she is 42 weeks according to the latest WHO guidelines , however hospitals are more and more frequently offering induction to pregnant woman from 39 week. First- time mums average 41.3 weeks of gestation so this doesn’t really make sense. Most elective inductions are offered to woman when they near their “due date”, this is usually determined via an ultrasound however they frequently change.

Have you ever heard, “My due date changed again!” Obviously the date of conception never changes, therefore, a due date is not a moving target. An ultrasound can be off by 2 whole weeks in either direction and up to 1kg in either direction. Each pregnancy is unique and term for one pregnancy could be 37 weeks and for another 42.3 weeks.

Not everyone has a 28 day cycle and not every mother will go into spontaneous labour at 40 weeks, in fact only 5% of women do. One size doesn’t fit all.

The more than you know, the more prepared you can be. When I’m doubt, use your brain Ask questions!! Use your BRAIN approach (what are the Benefits, Risks, Alternatives, what are your Instincts, what if you do Nothing). And finally, you can always ask…. 'Am I ok? Is the baby ok?' If the answer is yes, then you have time to go for a coffee, chat with your partner/doula and research the risks and benefits for yourself.