1. Clinical Institute; University of Southern Denmark; Odense Denmark
2. Department of Gynecology and Obstetrics; Odense University Hospital; Odense Denmark
3. Department of Obstetrics and Gynecology; Institute of Clinical Sciences; Gothenburg University; Gothenburg Sweden
4. Department of Genes and Environment; Norwegian Institute of Public Health; Oslo Norway
5. Division of Surgery; University College London; London UK
6. Department of Obstetrics and Gynecology; Clinical Sciences; Lund University; Lund Sweden