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A member asked:

What's more reliable for edd u/s at 8w1d or lmp? know lmp but they are going by ultrasound now...

A doctor has provided 1 answer

Ultrasound: dates are very good especially if the periods are regular. US is better because of the unreliability of the dates. That said both of the calculations will give you a date which is +/- 2 weeks, so there is very little difference between them and it is only statistical. The baby doesn't care and will come when it wants to.

Answered 8/28/2014

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Related Questions

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Why do doctors choose to go by ultrasound for EDD instead of LMP, even if LMP is known?

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I know when my lmp was but when they didn an ultrasound they gave me an edd of January 13 when it should be around December 31st?

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I have had 2 Ultrasound scans that show my EDD as 9th January and 7th January respectively. it doesn't tally at all with my LMP. A lot of weeks off. About 6-8 weeks?

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What if you know your LMP (which is regular 28 day cycle) but doctors change EDD going by first ultrasound. Why, did I ovulate later or what??

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Edd is 11/12 based on early ultrasounds & lmp. Possible i conceived on 2/7/13? How long is sperm viable in a woman?

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