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.
Ultrasounds performed after 22 weeks gestation cannot be used to estimate the due date of the baby because the size no longer reflects the age very well. Even average babies can differ by up to 2 to 3 weeks of growth;.These scans are only used to estimate the due date of your baby if this is all you have to go on. dating scan is an ultrasound examination which is performed in order to establish the gestational age of the pregnancy. Dating scans also reveal other important information such as: