Ultrasound accuracy dating conceive
Ultrasound uses the size of the fetus to determine the gestational age (the time elapsed since the the first day of the last menstrual period).
The accuracy of the ultrasound estimate of the gestational age varies according to the gestational age.
Determining the Estimated Due Date The estimated due date (EDD or EDC) is the date that spontaneous onset of labor is expected to occur. Conceptional age, menstrual age, and ultrasound age: a second-trimester comparison of pregnancies of known conception date with pregnancies dated from the last menstrual period.
The Doppler is usually used from about ten to twelve-weeks gestation until labor begins.
It can also be used in labor as a type of fetal monitoring.
However, your baby's heart will begin to beat between the fifth and sixth week of pregnancy.
The most common way to listen to the fetal heart beat is with a hand held Doppler device.
This listening device uses ultrasound technology, sound waves, to project the sound of your baby's heartbeat through a speaker.
"Ultrasound measurement of the embryo or fetus in the first trimester (up to and including 13 6/7 weeks of gestation) is the most accurate method to establish or confirm gestational age" .