A nuchal scan is a sonographic prenatal screening scan (ultrasound)The scan is carried out at 11–13.6 weeks pregnancy and assesses the quantity of fluid collecting within the nape of the fetal neck. There are two distinct measurements -- the nuchal translucency, which is measured earlier in pregnancy at the end of the first trimester, and for which there is a lower threshold for increased diameter, and the nuchal fold, which is measured towards the end of the second trimester. Fetuses with Down syndrome tend to have an increased amount of fluid around the neck
Posted on: Sat, 24 Aug 2013 23:05:17 +0000