1. Department of Obstetrics and Gynecology Haukeland University Hospital Bergen Norway
2. Research Group for Pregnancy, Fetal Development and Birth, Department of Clinical Science University of Bergen Bergen Norway
3. Department of Obstetrics and Gynecology Stavanger University Hospital Stavanger Norway
4. Center for Fetal Medicine Trondheim University Hospital (St. Olav's Hospital) Trondheim Norway
5. Department of Clinical and Molecular Medicine Norwegian University of Science and Technology Trondheim Norway
6. Department of Obstetrics and Gynecology Oslo University Hospital Oslo Norway
7. Institute of Clinical Medicine University of Oslo Oslo Norway