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A member asked:

How accurate is a 8 weeks ultrasound? can it shows 8 weeks but actually to be in 16 weeks? is if possible such a big error?

A doctor has provided 1 answer
Dr. Paul Velt answered

Specializes in Diagnostic Radiology

Not an error: This has to do with the way the dates are calculated and the standard deviation in the method. An 8 week ultrasound has a standard deviation of only 1 week at most. Not 8 weeks. When there is such a large difference it is usually because the dates that were given were wrong.

Dr Khaliq agreed

Answered 8/13/2014

3.8k views

Thank

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