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A member asked:

How are conception dates calculated if i don't have a regular 28 day cycle but had a transvaginal u/s done 6/11 dating me 6 weeks 3 days ?

6 doctors weighed in across 2 answers

Conception dates: If the sonogram determined that you are 6 weeks 4 days then you conceived 2 weeks 3 days ago. That is because obstetricians by convention date the pregnancy from last menstrual period.

Dr Higginbotham and 3 doctors agreed

Answered 7/30/2014

5.4k views

Thank

Subtraction: Subtract 4 weeks from the date of your 6w3d u/s, that will put you within a couple of days.

Answered 6/22/2017

5.4k views

Thank

Related Questions

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If your early dating ultrasound shows that my conception date is 18 days after my lmp, does that mean i ovulate late?

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Whats the error of margin for u/s dating at 11w4days on 01/20/14 with edd of 8/08/14 as far as conception date? Is 11/25/13 eliminated from conception

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A member asked:

I got a 6 week ultrasound, dating me for delivery 08, 29, 2013 so that would make my conception date in december correct?

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If labor/delivery occurs after your due date, did conception occur later than suspected from the dating ultrasound?

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People also searched for:

So would a transvaginal untrasound dating me at 7 weeks 3 days be early rather than late in guessing the date of conception?
How accurate are transvaginal ultrasounds in dating conception date if have irregular periods?
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