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A member asked:

Are the measurements that precise on ultrasounds that it can show the difference between a 12wk fetus and a fetus that is 12wks and 4 days?

3 doctors weighed in across 2 answers
Dr. Nikolaos Zacharias answered

Specializes in Maternal-Fetal Medicine

No.: At 12 weeks, the estimated accuracy of ultrasound measurements (crown-rump length or crl) is +/- 7 days. Take Folic Acid 1-5 mg daily and best of luck!

Dr Chuu agreed

Answered 10/24/2017

5.4k views

Thank
Dr. Bruce J. Stringer answered

Specializes in Radiology

NO: There are minor variations in how the measurements are made and differences in the size of different fetuses. These variations can easily account for a four day discrepancy.

Answered 12/18/2012

5.4k views

Thank

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