37 vs 40 weeks - which is full term?

[wondering7777]

I read on the NHS website that at 37 weeks, a pregnancy is considered to be full term and the baby is ready to be born. If that's the case, why is pregnancy always measured as 40 weeks? Shouldn't it be 37?

It's probably a really stupid question but it got me wondering!

Hey your not alone I've always been under the impression it's 40 weeks... And the reason they let you go 2 week over sometimes is because your not actually pregnant for the first 2 weeks... That was my logic anyway.
I'm having baby no3 and it's only when a sonographer said to me about 37 being classed as full term I got confused then I've also seen everyone on here saying same thing 🙈

I think 40 is standard but babies born from 37 weeks don’t usually need extra help, like steroids for lungs etc that babies born earlier may get/need.

37 weeks is considered 'term' before that you'd be treated as pre-term labour.

Anything from 37-40 weeks is full term. I a midwife and if baby is born before 37 weeks it is treated as preterm so will have a pathway to follow like for example antibiotics in labour, a paediatrician at delivery. After 37 weeks they will just be treated as normal.

I am expecting twins so will be having them at 37 weeks; so I’ve asked this question! Apparently 37 weeks is classed as term and babies are likely to be fully formed and healthy - but an extra 2-3 weeks in the womb can help certain organs develop that bit more before birth, lead to a ‘chunkier’ healthy birth weight, much less likely to have any health issues at birth, etc etc. So 37 weeks is fine; 40 even better - as far as I’ve been told!

As far as I understood it, baby is ready to be born from 37 weeks - I.e. wouldn’t need any extra help if born then, but if they stay in from 37-40 weeks and beyond they just get bigger. Perhaps it’s more complicated than that?!

So 40 weeks is term as in for due date and counting as overdue, but anything from 37 weeks baby would be fine being born

Thanks for the replies. I’m currently 20 weeks pg and was pleased to read it as it means that technically I only have 17 weeks left until the baby’s ready to be born, as opposed to 20. Although in reality it’ll probably be two weeks overdue, meaning I actually have 22 weeks left!