1. Center for High-Risk Pregnancy and Fetal Care, Department of Obstetrics and Gynecology , University of Chieti , Chieti , Italy
2. Department of Obstetrics and Gynaecology Fondazione Policlinico Tor Vergata Università Roma Tor Vergata , Roma , Italy
3. Fetal Medicine Unit, Saint George’s Hospital , London , UK
4. Department of Public Health , School of Medicine, Federico II University of Naples , Naples , Italy
5. Bürgerhospital Frankfurt am Main , Frankfurt am Main , Germany
6. Department of Clinical Science, Intervention and Technology , Karolinska Institutet and Center for Fetal Medicine, Karolinska University Hospital , Stockholm , Sweden
7. Women’s Health and Perinatology Research Group, Department of Clinical Medicine , UiT-The Arctic University of Norway , Tromsø , Norway
8. Department of Obstetrics and Gynecology , University Hospital of North Norway , Tromsø , Norway
9. Divisions of Maternal-Fetal Medicine and Clinical Research, Department of Obstetrics and Gynecology , Washington University School of Medicine , St. Louis , MO , USA