1. Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Goteborg, Sweden
2. Department of Clinical Sciences, Obstetrics and Gynecology, Umeå University, Umeå, Sweden
3. School of Medicine Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
4. Department of Obstetrics and Gynaecology, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Sahlgrenska University Hospital, Goteborg, Sweden