1. Aga Khan University Hospital; Department of Obstetrics & Gynaecology; Nairobi Kenya PO Box 30270-00100 GPO
2. University of Southampton; Obstetrics and Gynaecology; Level F, Princess Anne Hospital Coxford Road Southampton UK SO16 5YA
3. University of Rochester School of Medicine & Dentistry; Department Obstetrics & Gynecology; 601 Elmwood Avenue, Box 668 Rochester New York USA NY14642
4. St Bartholomew's Hospital; Centre for Reproductive Medicine; Little Britain London UK EC1A 7BE