Garthwaite M1, Varley C1, Marsh F2, Ramage C3, Urwin G4, Eardley I5, Trejdosiewicz L6, Southgate J1 1. Department of Biology, University of York, 2. Department of Obstetrics and Gynaecology, St. James's University Hospital, Leeds, 3. Department of Obstetrics and Gynaecology, Bradford Royal Infirmary, 4. Department of Urology, York Hospital, 5. Department of Urology, St. James's University Hospital, Leeds, 6. Cancer Research UK Clinical Centre, St. James's University Hospital, Leeds