[1] Univ Coll London Hosp NHS Fdn Trust, Dept Haematol, London, England
[2] UCL, Dept Haematol, Haemostasis Res Unit, 51 Chenies Mews, London WC1E 6HX, England
[3] Univ Amsterdam, Dept Vasc Med, Acad Med Ctr, Amsterdam, Netherlands
[4] Tech Univ Dresden, Univ Hosp Carl Gustav Carus, Ctr Vasc Med, Dresden, Germany
[5] Tech Univ Dresden, Univ Hosp Carl Gustav Carus, Dept Med 3, Dresden, Germany
[6] UCL, Dept Obstet & Gynaecol, London, England
[7] Royal Free Hosp NHS Fdn Trust, Katharine Dormandy Haemophilia Ctr, London, England
[8] Royal Free Hosp NHS Fdn Trust, Thrombosis Unit, London, England
[9] Royal Free Hosp NHS Fdn Trust, Dept Obstet & Gynaecol, London, England