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A member asked:

Can you accurately calculate date of conception if you have irregular cycles? early us & 6w 1d said edd was 4/16. 14 weeks later @ 20w edd said 4/13.

A doctor has provided 1 answer

Conception: It is not possible to calculate with certainty both due to your irregular periods and the limits of ultrasound dating, meaning it is always +/- at least a few days. If you are trying to determine paternity, you will have to do so post birth.

Answered 12/25/2014

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Related Questions

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How accurate are trans-vaginal u/s at 9wks & 6days? Do they go back to your LMP or conception date? My edd is 1/22/13, from my 1st vaginal u/s...

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With these dates who would u say the father is.Conception w/ f#1 6/17/13. Conception w/ f#2 almost everyday. Edd by us=3/18/14 both pulled out...

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Whats the error of margin for u/s dating at 11w4days on 01/20/14 with edd of 8/08/14 as far as conception date? Is 11/25/13 eliminated from conception

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My edd is 1/22/13, when is the likely-hood of my conception date? Could it have been around april 6-8, being my edd is 1/22/13?

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If LMP and first trim scans all point to same EDD, is the conception date range accurate?

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