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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

Yes: Ultrasound for pregnancy uses the same 40 week gestation time as OB to be consistent. So, the reference date is the time of the last menstrual period, not ovulation. Honestly, i don't know why the medical community hasn't changed this except that it has been accepted for so long.

Dr Ali and 2 doctors agreed

Answered 5/16/2015

4.1k views

Thank

Related Questions

A member asked:

I got my first ultrasound at 16 weeks. My LMP came to december 5th and conception date was december 19th. Is it possible i could of conceived jan 10?

A doctor has provided 1 answer

A member asked:

If my ultrasound matches lmp, when would I most likely have conceived?

A doctor has provided 1 answer

A member asked:

What does it mean if LMP and early ultrasound match by 5 days? Does that mean i for sure conceived within + or - 7 days of that date?

A doctor has provided 1 answer

A member asked:

If my lmp and ultrasound match to exact date does that mean I conceived 2 weeks after my lmp?

A doctor has provided 1 answer

A member asked:

Hi! Do ultrasounds typically measure from the first day of my lmp? Would that mean I conceived before my lmp or after? Asking because my ultrasound and lmp dates match, thank you in advance?

A doctor has provided 1 answer

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