1. Department of Obstetrics and Gynecology; Helsinki University Hospital; FI-00029 HUS Finland
2. Finnish Cancer Registry; Institute for Statistical and Epidemiological Cancer Research; Unioninkatu 20 Helsinki FI-00130 Finland
3. School of Health Sciences; FI-33014 University of Tampere; Finland
4. Public Health-Cancer Policy Support; European Commission DG Joint Research Centre, Institute for Health and Consumer Protection; Ispra I-21027 Italy