1. Department of Obstetrics and Gynaecology; University Hospital of Northern Norway; Tromsø Norway
2. Women's Health and Perinatology Research Group, Department of Clinical Medicine, Faculty of Health Sciences; UiT - The Arctic University of Norway; Tromsø Norway
3. Department of Obstetrics and Gynaecology; University of Chieti; Chieti Italy
4. Department of Obstetrics and Gynaecology; Arnas Civico Hospital; Palermo Italy
5. Fetal Medicine Unit, Division of Developmental Sciences; St George's University of London; London UK
6. Local Health Unit of Pescara; Pescara Italy
7. Department of Morphology, Surgery and Experimental Medicine; University of Ferrara; Ferrara Italy
8. Department of Obstetrics and Gynaecology; Catholic University of The Sacred Heart; Rome Italy
9. Department of Medical Sciences; University of Ferrara; Ferrara Italy