Skip to main content. Am J Obstet Gynecol ; Most dating scans are done with a trans-abdominal transducer and a fullish bladder. Safety of 3D ultrasound from AskQuestions. A dating scan is an ultrasound examination which is performed in order to establish the gestational age of the pregnancy. Fetal Ultrasound Online Peter W. Check here for alerts.
Int J Gynaecol Obstet ;
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This is because the fetus is growing so quickly that there is a big difference in size from week to week. Mean sac diameter measurements are not recommended for estimating the due date. What can be seen?