Combined first trimester screening in Denmark and the Danish Fetal Medicine Database

All pregnant women in Denmark are offered a first-trimester ultrasound screening examination between 11 and 14 weeks of gestation. Additionally, women are offered a risk assessment for foetal chromosomal abnormalities. The main results in this review are that more than 90% of pregnant women attend the first-trimester screening, and of those, 5% receive a high-risk screening result for trisomy 21. The first-trimester screening detects more than 90% of trisomy 21 cases and a large proportion of...