In an effort to allow for this discrepancy, many baroque ensembles adjust their tuning to the repertoire being performed: aâ= 415hz for late baroque music, aâ=392hz for French music, aâ=440hz for early Italian music and aâ=430hz for classical repertoire.
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.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 [24].ltrasound 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.
Doctors use various methods to determine gestational age of a pregnancy. The most common test is the ultrasound, which measures the size of the gestational sac and the length between crown and rump to determine the age of the fetus in weeks. Last Menstrual Period: Using the first day of your last menstrual cycle, gestational age can be determined (plus or minus 2 weeks.) The doctor adds 280 days to the first day of your last menstrual cycle to determine a due date.