1. Fetal Medicine Unit, St George’s University Hospital NHS, London, United Kingdom
2. Department of Obstetrics and Gynaecology, City Hospital Triemli Zurich, Switzerland
3. Department of Obstetrics and Gynecology, New York University School of Medicine, USA
4. Sevisa AG, Ermatingen, Switzerland
5. Pränatal Zürich, Zurich, Switzerland, and Medical Faculty, Heinrich Heine University, Düsseldorf, Germany