1. Department of Obstetrics and Gynaecology, Simpsons Centre for Reproductive Health, Royal Infirmary of Edinburgh, Edinburgh, UK
2. Department of Gastroenterology, Division of Medicine, Royal Infirmary of Edinburgh, Edinburgh, UK
3. Division of Surgery, University College London, Northwick Park Institute of Medical Research Campus, London, UK
4. Institute of Clinical Research, University of Southern Denmark, Odense, Denmark