Nuchal translucency (NT) and nuchal fold thickening are two distinct soft markers for fetal abnormalities and aneuploidy.
The nuchal translucency is the normal fluid-filled space located at the back of the baby’s neck, and it is scanned via ultrasound during the first trimester. An increased nuchal translucency is considered a marker for fetal anomalies and can be associated with chromosomal abnormalities like trisomy 13, trisomy 18, trisomy 21 (Down syndrome), and Turner syndrome as well as structural defects like congenital diaphragmatic hernia, congenital heart defects, omphalocele, and skeletal dysplasia. A nuchal translucency scan is usually combined with other testing like maternal serum screening. Based on the results of these tests, more invasive diagnostic tests like amniocentesis and chorionic villus sampling (CVS) may be recommended.
The nuchal fold is the normal fold of skin located at the back of the baby’s neck, and it is scanned via ultrasound during the second trimester. An increased thickness of the nuchal fold is considered a marker for abnormalities and can be associated with chromosomal abnormalities like trisomy 13, trisomy 18, trisomy 21 (Down syndrome), and Turner syndrome as well as congenital heart defects. [49]