[1] Royal London Hosp, Barts Hlth NHS Trust, London, England
[2] British Undergrad Soc Obstet & Gynaecol, London, England
[3] Chelsea & Westminster Hosp NHS Fdn Trust, London, England
[4] Queen Mary Univ London, London, England
[5] Lister Hosp, East & North Herts NHS Trust, Stevenage, Herts, England
[6] Imperial Coll London, London, England
[7] Newcastle Univ, North Cumbria Integrated Care Trust, Newcastle, England