1 doctor weighed in:

Can 1st trimester u/s be off 3 weeks in gestational age and in conception? (1st trimester) even if they have been pretty consistent in the pregnany

1 doctor weighed in
Dr. David Doucette
Obstetrics & Gynecology

In brief: Not usually

Generally, the best ultrasound for dating is an early first trimester ultrasound.
It is unlikely to be off by that much from where the actual pregnancy dates are, but it might be off from your menstrually calculated due date due to issues with when your last period was.

In brief: Not usually

Generally, the best ultrasound for dating is an early first trimester ultrasound.
It is unlikely to be off by that much from where the actual pregnancy dates are, but it might be off from your menstrually calculated due date due to issues with when your last period was.
Dr. David Doucette
Dr. David Doucette
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