[1] IRCCS Ca Granda Fdn Maggiore Policlin Hosp, Sci Direct, I-20122 Milan, Italy
[2] Univ Edinburgh, Ctr Reprod Biol, Edinburgh EH8 9YL, Midlothian, Scotland
[3] Hosp Univ Quiron Dexeus, Dept Obstet Ginecol & Reprod, Barcelona, Spain
[4] Univ Aberdeen, Aberdeen Matern Hosp, Sch Med & Dent, Reprod Med, Aberdeen, Scotland
[5] Univ Aberdeen, Aberdeen Matern Hosp, Sch Med & Dent, Div Appl Hlth Sci, Aberdeen, Scotland
[6] Univ Aberdeen, Aberdeen Matern Hosp, Sch Med & Dent, Inst Appl Hlth Sci, Aberdeen, Scotland
[7] Vrije Univ Brussel, Univ Ziekenhuis, Ctr Reprod Med, Brussels, Belgium
[8] Maastricht Univ, Med Ctr, Dept Obstet Gynecol, Maastricht, Netherlands
[9] SISMER, Reprod Med Unit, Bologna, Italy
[10] IRCCS Ca Granda Fdn Maggiore Policlin Hosp, Clin Ostetr & Ginecol, Milan, Italy
[11] Univ Helsinki, Helsinki Univ Hosp, Dept Obstet & Gynaecol, Helsinki, Finland
[12] Univ Oulu, Oulu Univ Hosp, Dept Obstet & Gynaecol, Oulu, Finland
[13] Med Res Ctr Oulu, Oulu, Finland
[14] Univ Amsterdam, Acad Med Ctr, Womens & Childrens Hosp, NL-1105 AZ Amsterdam, Netherlands
[15] Univ Klinikum Schleswig Holstein, Klin Frauenheilkunde & Geburtshilfe, Kiel, Germany
[16] Kings Coll London, Sch Biomed & Hlth Sci, Reprod & Rhythms Grp, London WC2R 2LS, England
[17] Univ Maastricht, Dept Genet & Cell Biol, Maastricht, Netherlands
[18] Sahlgrens Univ Hosp, Reprod Med, Gothenburg, Sweden
[19] Univ Trondheim, Dept Ob & Gyn, N-7034 Trondheim, Norway
[20] Aristotle Univ Thessaloniki, Sch Med, Dept OB GYN 1, Human Reprod Unit, GR-54006 Thessaloniki, Greece
[21] R D Hosp Univ Quiron Dexeus, Barcelona, Spain