[First trimester ultrasound screening for fetal anomalies--classics and novelties].

The aim of this paper is to provide an up-to-date review of the possibilities for ultrasound screening for chromosomal and structural fetal anomalies in the first trimester. The major ultrasound and biochemical markers used in the assessment of risk for fetal abnormalities between 11+0-13+6 w.g. are described. The role of the first trimester fetal morphology scan in the in the echographic follow up of the pregnancy is discussed.