U.S. doctors online nowAsk doctors free
Oakland, CA
A 30-year-old female asked:

Do ultrasounds add two preconception weeks when measuring baby? if baby measures 12 w is this supposed to date to lmp or conception?

1 doctor answer1 doctor weighed in
Dr. Robert Kwok
Pediatrics 35 years experience
Yes. LMP.: The gestational age (number of weeks pregnant) stated in the result of the ultrasound already added the 2 preconception weeks. If the ultrasound dating says 12 weeks gestation, that means 12 weeks since the estimated start of the last menstrual period (lmp).
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Mar 2, 2014


Content on HealthTap (including answers) should not be used for medical advice, diagnosis, or treatment, and interactions on HealthTap do not create a doctor-patient relationship. Never disregard or delay professional medical advice in person because of anything on HealthTap. Call your doctor or 911 if you think you may have a medical emergency.