1. St Mary's Hospital; Reproductive Medicine; Hathersage Road Manchester UK M13 0JH
2. Queen Charlotte's and Chelsea Hospital; Imperial College Healthcare Trust London UK
3. University of Nottingham; Division of Child Health, Obstetrics and Gynaecology, School of Medicine; D Floor, East Block, Queens Medical Centre Nottingham UK NG27SE
4. University of Warwick; Clinical Sciences Research Institute; Coventry UK CV4 7AL