That depends: How early did you get your earliest ultrasound? If it was in the first 12 weeks, then the possible error is no more than 4 days+/-. If it was later, the ultrasound size may be off by a little more. We count from the last menstrual period because in the past we did not have ultrasound and the period was the only landmark we had to go on to date a pregnancy. Was there another partner?
Answered 4/25/2015
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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