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A member asked:

Do ultrasounds add two weeks to date back to (or close to) your lmp?

A doctor has provided 1 answer
Dr. Robert Kwok answered

Yes: That is how doctors count the number of weeks pregnant. We all count from the estimated start of the last menstrual period. All dates are estimates, which works fine in almost all cases.

Answered 2/21/2014

4.4k views

Thank

Related Questions

A member asked:

Do ultrasounds date from conception or lmp? I.E. If they say baby measures 12 weeks, is that from conception or should that date back to your lmp?

A doctor has provided 1 answer

A member asked:

Don't need to pinpoint conception day, but two first trim ultrasound give same due date we have no lmp to go off, how accurate is age of our baby?

A doctor has provided 1 answer

A member asked:

Are two weeks added to ultrasound gest. Age like when calculating from the lmp? Eg, u/s on jan 13 estimated 9+1 age. So i conceived roughly nov 9?

A doctor has provided 1 answer

A member asked:

I had sex with two guys 10 days apart, one on 11 Feb, and one on 20 Feb. My due date was 12 Nov from ultrasound and 13 Nov from LMP.. Im not sure who the dad is?

A doctor has provided 1 answer

A member asked:

I had my period on April 9th. My periods are fairly irregular by a week or so. My ultrasounds measure two weeks behind my LMP due date. I've had one done at 5WKS (too small to tell), 6WKS5DYS, & 19WKS. They all gave me the same due date by except 2 days.

A doctor has provided 1 answer

People also searched for:

Do ultrasounds add two weeks & should they theoretically date back to your lmp?On 12/6/13 baby measured 12w4d, crl was 60.9mm.If go back 12w4d should that date to(or close to) my lmp?When was conceptn?
Do ultrasounds add two preconception weeks when measuring baby? If baby measures 12 w is this supposed to date to LMP or conception?
My ultrasounds date back to my (estimated) date of conception rather than the first day of my LMP. Is this normal?
I have two due dates based on my LMP and and ultrasound. Which one is more accurate?
1st ultrasound says crl 8mm 6w5d. 2nd says crl 28mm, 9w4d. 3rd , crl 60.9mm 12w4d.Are these supposed to date back to lmp? When was conception?

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