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A 32-year-old female asked:

Had ultrasound on nov.20, 2012 putting me at 12weeks and 4 days. last period was aug. 27. due date may.31. when would i have conceived?

1 doctor answer1 doctor weighed in
Dr. Bruce J. Stringer
Radiology 48 years experience
Around Sept. 7: Using the ultrasound dating, conception occurred around sept. 7. Intercourse could have been 48-72 hours prior to this. Remember that there is a certain error around the ultrasound dating of around a week as well! hope this helps.
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Last updated Jun 22, 2017

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