A 29-year-old female asked:
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Why are ultraound edd more accurate than your LMP edd?

1 doctor answer
Dr. Padmavati Garvey
29 years experience in Obstetrics and Gynecology
They are not: Ultrasound based edd were established by doing ultrasound measurements on women who absolutely knew when they conceived. Thus they are just as accurate as a very accurate lmp. Some women do not remember an accurate lmp.
Answered on Dec 20, 2012
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1 comment
Dr. Padmavati Garvey
29 years experience in Obstetrics and Gynecology
Provided original answer
Sometimes when you actuallly conceived is not exactly the time that you would expect based on your LMP or could be a few days after you have ovulated. The women they used to establish ultrasound measurements initially were women who had gone through invitro fertilization or women who had had sex only once in a given month, etc.
May 26, 2011

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