1. Department of Obstetrics and Gynaecology; Barking, Havering and Redbridge University Hospitals NHS Trust; Romford Essex RM7 0AG UK
2. Department of Obstetrics and Gynaecology; North Middlesex University Hospital NHS Trust; Sterling Way London N18 1QX UK
3. Royal Marsden Hospital; Fulham Road London SW3 6JJ UK
4. St George's Hospital; Tooting London SW17 0QT UK