1. Department of Obstetrics and Gynaecology Institute of Clinical Sciences Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
2. Regional Cancer Centre West Region Västra Götaland Gothenburg Sweden
3. Department of Oncology Institute of Clinical Sciences Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
4. Department of Medical Epidemiology and Biostatistics Karolinska Institutet Stockholm Sweden