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How do you know how far you are in pregnancy?

(9 Posts)
laurenmarie88 Mon 26-Dec-16 08:27:37

Hi all, just going by the first day of my last period and it says I'm 5 weeks pregnant but my last period was around 16/17 November so how do they work it out ? Thanks fsmile

Want2bSupermum Mon 26-Dec-16 08:31:30

You should have a scan that dates your pregnancy. I'm in the US so it's at what they think is 8 weeks. Based on that scan you go for blood work and detailed scan at 12 weeks (no later than 13wks and 5 days as I learned with my first when my 8 week appointment turned out to be 10 weeks!).

bluecashmere Mon 26-Dec-16 08:31:53

Not quite sure what your question is but you'll have an estimated expected date from your booking appointment that will be adjusted if necessary when you have your first scan.

NerrSnerr Mon 26-Dec-16 08:36:27

This is what they will initially go by and then at your 12 week scan they'll give a more accurate date.

WishUponAStar88 Mon 26-Dec-16 08:39:08

Initial date is 40 weeks from last period. If in the U.K. you'll have a dating scan around 12weeks which will give your actual due date. Congratulations, I hope this is happy news for you smile

laurenmarie88 Mon 26-Dec-16 11:32:33

In the U.K. And I remember my last period but was just wondering how they work out your dates, because when I went on the pregnancy calculator it estimated I was around 5 weeks but I just don't understand how they do it haha thanks for your answers xx

MouseLove Mon 26-Dec-16 14:30:15

5 weeks ago was around the 16/17 November plus 5 days for your actual period. That's how they date it until you have your dating scan. Then it will be dated from conception, which is when sperm met egg.

MoonlightMojitos Mon 26-Dec-16 16:49:59

It's always 2 weeks (roughly) on top of conception. So you are already 2 "weeks pregnant" when you conceive. It's confusing but just the way it's done! So your due date will be 40 weeks pregnant but that's actually 38 weeks from conception. As others have said they'll confirm a date at your scan which is based on baby's crown to rump measurement.

laurenmarie88 Mon 26-Dec-16 17:58:33

Haha it's all very confusing isnt it, can't wait to find out when we have our first scan just suppose it's a waiting game now xx

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