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A member asked:

Don't need to pinpoint conception day, but two first trim ultrasound give same due date we have no lmp to go off, how accurate is age of our baby?

A doctor has provided 1 answer

Accurate estimates: Ultrasound dating scans in the first trimester, such as at 8-11 weeks of pregnancy, are very accurate... meaning plus or minus one week. Especially if the doctor feels the fetus is growing appropriately for gestational age through the course of the pregnancy, the original dating estimates were likely very accurate.

Answered 6/23/2017

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Related Questions

A member asked:

What is my dates of conception if LMP is Oct. 13 2014 and first ultrasound at 9 weeks gave me a due date of July 25 2014?

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A member asked:

Do ultrasounds date from conception or lmp? I.E. If they say baby measures 12 weeks, is that from conception or should that date back to your lmp?

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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?

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A member asked:

First ultrasound on 12/10/12 dated at 8 weeks and estimated my unknown LMP to be 10/15/12. Is it at all possible conception happened after 11/14/12?

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How accurate are ultrasounds? With conception date LMP 4/25/14 30 daycycle lasted 4 days DueDate 1/30/15 according to 8wk 4day ultrasound on 6/24/14

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