1. Department of Obstetrics and Gynecology; Clinical Sciences; Lund University; Lund Sweden
2. Department of Obstetrics and Gynecology; Landspitali University Hospital; Reykjavik Iceland
3. Center for Fetal Medicine; Trondheim University Hospital (St Olavs Hospital); Trondheim Norway
4. Institute of Clinical and Molecular Medicine; Norwegian University of Science and Technology; Trondheim Norway