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A member asked:

Some say that fetal ultrasound measurements @ 12 weeks can be off by 2weeks. some say a few days (+\-5 days). which is it? do radiologists know best?

2 doctors weighed in across 2 answers

See below : The younger the fetus, the more accurate the measurement. Radiologists are the accepted specialists for ultrasound.

Answered 4/7/2013

5.2k views

Thank

Accuracy: At 12 weeks is +/-3-5 days if crown rump measurement is used.

Dr Sparacino agreed

Answered 1/30/2014

5.2k views

Thank

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