[1] UNIV HELSINKI,CENT HOSP,DEPT OBSTET & GYNAECOL,SF-00290 HELSINKI 29,FINLAND
[2] HELSINKI RES CTR,HELSINKI,FINLAND
[3] RN LAAKARIKESKUS TAMPERE,TAMPERE,FINLAND
[4] LAAKARIKESKUS SYYNI,KUOPIO,FINLAND
[5] UNIV KUOPIO,DEPT PATHOL,KUOPIO,FINLAND
[6] ROCHE BASEL,BASEL,SWITZERLAND
[7] ROCHE PROD LTD,WELWYN GARDEN CIT AL7 3AY,HERTS,ENGLAND
[8] ROCHE OY,ESPOO,FINLAND
[9] CLIN RES & COMMUN,BASEL,SWITZERLAND