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What is the accuracy of an abdominal ultrasound at 7 weeks? Is it greater than the standard of +/- a wk for 1st trimester since preformed abdominally?

5 doctors weighed in
Dr. Steven Chmielewski
Diagnostic Radiology
4 doctors agree

In brief: Probably not.

First trimester ultrasound is accurate to about a week.
This algorithm is based primarily on crown rump length. The date is as accurate as the measurement. That being said, a transvaginal exam is probably a bit more accurate, but it's only as good as the measurement.

In brief: Probably not.

First trimester ultrasound is accurate to about a week.
This algorithm is based primarily on crown rump length. The date is as accurate as the measurement. That being said, a transvaginal exam is probably a bit more accurate, but it's only as good as the measurement.
Dr. Steven Chmielewski
Dr. Steven Chmielewski
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