[1] KINGSTON GEN HOSP,DEPT HAEMATOL,KINGSTON HULL HU3 1UR,N HUMBERSIDE,ENGLAND
[2] UNIV LEEDS,SCH MED,DIV CLIN SCI,LEEDS LS2 9JT,W YORKSHIRE,ENGLAND
[3] UNIV EDINBURGH,DEPT OBSTET & GYNAECOL,CTR REPROD BIOL,EDINBURGH EH3 9EW,MIDLOTHIAN,SCOTLAND
[4] OXFORD BROOKES UNIV,SCH BIOL & MOLEC SCI,OXFORD OX3 0BP,ENGLAND