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A member asked:

Is u/s dating in first trimester more accurate that going by lmp? edd changed & going by ultrasound now...

A doctor has provided 1 answer

Depends: 1st trimester US is accurate within 5-7 days so if it differs from your LMP due date by more than that then the US is used. Also if you are uncertain about your LMP, most OB's will use that early US.

Dr Martin agreed

Answered 8/30/2014

3.8k views

Thank

Related Questions

A member asked:

What changes a due date? And why is the first trimester ultrasound more accurate than the second trimester ultrasound?

A doctor has provided 1 answer

A member asked:

How accurate are abdominal ultrasounds in first trimester for dating how far along you are?

A doctor has provided 1 answer

A member asked:

I wanted to know how accurate early ultrasounds (first trimester) are in conception dating? If i was 5 weeks4days 9/23/13 putting conception 25-28 of aug could I have still concieved 7/28/13

4 doctors weighed in across 2 answers

A member asked:

What if you know your LMP (which is regular 28 day cycle) but doctors change EDD going by first ultrasound. Why, did I ovulate later or what??

3 doctors weighed in across 2 answers

A member asked:

What is EDD (LMP) and EDD (AUA)? And which is more accurate when done in the first trimester; 7-8weeks?

A doctor has provided 1 answer

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People also searched for:

LMP was Feb 18, I have shorter cycles of 25/26 days. 3 first trimester ultrasounds gave me a due date of Nov 19-21 putting conception at Feb 27-29. How accurate are these conception dates? Anyway conception occurred before February 20?
What does it mean when LMP dating by ultrasound in first trimester assumes a 28 day cycle?
Had a dating ultrasound i was 14w3d. Couldnt use LMP i was on depo,I wasnt having periods. Can edd be off by 2w3d at 14 week ultrasound.How accurate?
What do dating ultrasounds date? Conception, lmp, or due date?
If you ovulate later than the normal 14 days after lmp, would the dating ultrasound this and would it affect your due date?

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