New Zealand Obstetric Ultrasound Guidelines 2019

12 and 13+6 weeks gestation (see below) for optimal assessment of fetal anatomy and nuchal translucency (NT). The purpose of the scan is to confirm viability, accurately establish gestational age, determine the number of viable fetuses, evaluate gross fetal anatomy and, if requested, assess the NT as part of the risk assessment for aneuploidy. ................
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