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A member asked:

Lmp on 10/31or11/1/13 u/s 1/20 measured 11w3to4d. u/s on 3/28 measured 21w3d. accuracy? conception day? could 11/25 be conception? 30 day cycles

A doctor has provided 1 answer

11/14-11/15: Your first ultrasound is more accurate that the later one. The first ultrasound gives a conception date of 11/14-11/15. First trimester ultrasounds have an error rate of approximately one week (max). So that essentially rules out the possibility of an 11/25 conception date.

Dr Paudel agreed

Answered 4/2/2014

4.3k views

Thank

Related Questions

A member asked:

Conception would not be able to occur on 11/10/12 if the LMP was given as 10/15/12 and an estimated due date of 7/22/13 right?

A doctor has provided 1 answer

A member asked:

My LMP was April 28, conception May 12th, due date February 2nd. Was with guy 1 May 7th and Guy 2 May 12-13 who's the father most likely?

2 doctors weighed in across 2 answers

A member asked:

How accurate is an early ultrasound? On 6/15/18 baby measured 5w6d. Between what dates could conception of happened? LMP 5/5.

A doctor has provided 1 answer

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?

A doctor has provided 1 answer

A member asked:

Is the age shown on an ultrasound measured from LMP or conception? The US said 5w1d. If this is from LMP, conception would be after I got a pos. test

A doctor has provided 1 answer

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