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'Guesstimated' due dates

Tags: pregnancy, induction

39weeks: - So! You’re pregnant and the end is insight, you can almost smell the sweet smell of the top of your baby’s head and can’t wait to hold them in your arms.

40weeks: - Eeek! It’s nearly time! They’ll be here soon! Hospital bag is by the door, you’ve got your birth preferences printed out, baby’s going home outfit packed and the tiny little newborn nappies that make you want to cry when you look at them

40weeks 3days: - Well bubba’s obviously just comfy in there! No, great-aunty Joan, baby’s not here yet, yes of course I’ll let you know when they make an appearance.

40weeks 5days: - Starts Googling “is it possible to be pregnant forever?”

41weeks 2days: - deletes all social media accounts, DON’T EVEN LOOK AT ME!!!


That magical date has been in your diary and etched on your brain since your first scan, you excitedly took to social media to announce the date your little bundle would arrive (more on this later!) and crossed weeks off your calendar.

But now your due date has come and gone you’re feeling less than magical. I know this feeling all too well, my girls were born at 42+4 and 42+1 respectively and my little boy was born at 42+4. I hurt, I ached, I wanted to punch sweet old people who dared to smile at me and ask me when I was due.

It’s so hard to see your due date come and go, especially as a first time mum but the thing to remember is only 4% of babies are born on their due dates. ‘Term’ is classed as anything from 37weeks up to 42weeks which means you have a due month! So even if you reach and pass 40week your baby’s not classed as late. The average gestation for a first time mum to give birth at 41+1 and mums who are on their second or subsequent babies at 40+6.

And anyway, what are we basing this on? It does seem strange that we hold on to this magical date and hold so much stock in it when most of us are unsure about where it comes from. The calculation is called Naegele’s Rule and was devised by Professor of Obstetrics Franz Naegele in 1812. It is based on a 28 day menstrual cycle and with ovulation happening on day 14. If anyone has tracked their cycle before they’ll know that there can be a lot of variation to this. My cycles have always been 30-34 days long and think this might have led to my longer than average pregnancies.

In the UK, most trust will offer a membrane sweep to “nudge things along” at around 40weeks and then induction of labour at 41+5. I use the word “offer,” purposefully as this, as with anything else in pregnancy and labour is a choice and you can say no. A membrane sweep involves your midwife/consultant inserting their finger into your cervix and then ‘sweeping’ their finger around to separate the baby’s amniotic sac from your cervix, this is supposed to release prostaglandins which can encourage labour. It can be painful and lead to cramping and slight bleeding and could inadvertently rupture your membranes.

If you do reach 42weeks (only 7% of pregnancies will) and you would still like to refuse induction you should be offered expectant management which involves extra checks including scans to check placenta function, cord blood flow and the amount of fluid you have (scans to estimate baby’s size at this point have a large margin for error). Everything is your choice.

If there’s one piece of advice I’d give to first time mums, it would be to give your nearest and dearest a “due month” (and maybe move it forward a few days!) There’s nothing worse than when you’re trying to relax waiting for bubba to arrive at 40+3 and Tracey your third cousin twice removed (you saw her last at a christening 11years ago) texts saying she can’t wait to come and meet your baby (best wear a carnation for recognition though as there’s no way she’d be able to pick you out of a line up!)

And also remember – medical advice, it just that, advice, it’s up to you whether you follow it or not. Inform yourself, do your research, and decide from there.


Rach xx


Me at 42 weeks with my first                                                                                                                                                             Me at 42weeks with my second