[1] Guys Hosp, Guys Kings & St Thomas Med & Dent Sch, Dept Immunobiol, London SE1 9RT, England
[2] Guys Hosp, Guys Kings & St Thomas Med & Dent Sch, Dept Tissue Typing, London SE1 9RT, England
[3] Royal London Hosp, Dept Gynaecol, London E1 2AD, England
[4] St Marys Hosp, Imperial Coll, Dept Obstet & Gynaecol, Fac Med, London W2 1PG, England