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A member asked:

Why my dr change due date from 07/13 to 07/27 after ultrasound 1st date was based off period.. which date is more accurate went from 10wks to 8wks?

A doctor has provided 1 answer

Ultrasound: The earlier the ultrasound is done, the more accurate it is. Ultrasounds are more accurate than dating by menstrual periods. An ultrasound done at 8 weeks, such as yours, has an error of 0-1 days. Your due date given by your 8 week ultrasound it your actual due date.

Answered 6/13/2015

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