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A 22-year-old female asked:

Fetus was measuring accurate at 5w3d and 8w4d u/s. but this time i should be 11w3d but u/s showed only 10w1d with a strong heartbeat. why?

1 doctor answer1 doctor weighed in
Dr. Jeff Livingston
Obstetrics and Gynecology 23 years experience
Margin of error: There are various margins of error at various gestational ages on sonograms. The margin of error in a first trimester sonogram is about 7 days. You can confirm with your doctor but it appears you are within the normal range
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Last updated Aug 10, 2018


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