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A member asked:

When a doctor says margin of error is 3-5 days in first trimester us are they talking about lmp, due date, or conception date?

A doctor has provided 1 answer

Age of gestation: Age of gestation (age of fetus) is determined by the size of the fetus by us during the first trimester.

Answered 3/21/2019

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Related Questions

A member asked:

Hi doctors i had a ultrasound yesterday it said due aug 29 what is more accurate LMP or ultrasound i need my most accurate conception date please help?

A doctor has provided 1 answer

A member asked:

When does it mean when a doctor considers the LMP due date and conception if the ultrasound is in a 7-10 day agreement with the lmp? Need an example

A doctor has provided 1 answer

A member asked:

What if i don't know my LMP how will a doctor determine my conception date?

A doctor has provided 1 answer

A member asked:

I had a misscarriage at 15weeks in the 2nd trimester. Should i talk to my doctor about ic (cervix) as maybe a cause for the misscarriage?

A doctor has provided 1 answer

A member asked:

If my LMP according to my first US at 9 weeks was a day off from what I told the doctor is there still a 5 day error margin?

A doctor has provided 1 answer

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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?
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