1. The University of Adelaide, Women's and Children's Hospital; School of Paediatrics and Reproductive Health, Discipline of Obstetrics and Gynaecology; 72 King William Road Adelaide South Australia Australia 5006
2. Royal Liverpool University Hospital; Department of Genito-urinary Medicine; Prescot Street Liverpool UK L7 8XP
3. Division of Health Sciences, Warwick Medical School, The University of Warwick; Warwick Clinical Trials Unit; Gibbet Hill Road Coventry UK CV4 7AL