[Webbing of the neck and nasal bone--prenatal screening for Down syndrome]. / Nakkefold og naeseben--praenatal screening for Downs syndrom.

The risk of giving birth to a child with Down syndrome increases with maternal age. If in Denmark the mother is older than 35-years she belongs to a high-risk group and will be offered amniocentesis or chorionic villus sampling. We describe different scenarios of risk calculation for Down syndrome based on combinations of nuchal translucency, nasal bone, and/or integrated hormone test. The combination of nuchal translucency and visualisation of the nasal bone between gestational age 11 weeks and 13 + 6 has turned out to be as good a predictive marker as nuchal translucency and integrated hormone test.