1. From the Division of Women's Health (H.D.M., L.A.M., R.M.T.), King's College London and King's Health Partners, London, United Kingdom; Department of Obstetrics and Gynaecology (L.O.K., F.B.P.), University of Nottingham, Nottingham, United Kingdom; Basic Medical Sciences (I.A.G.), St George's University of London, London, United Kingdom.