[1] Vrije Univ Brussel, Univ Ziekenhuis Brussel, Ctr Reprod Med, Laarbeeklaan 101, B-1090 Brussels, Belgium
[2] Univ Modena & Reggio Emilia, Mother Infant Dept, Inst Obstet & Gynecol, I-41100 Modena, Italy
[3] Skive Reg Hosp, Fertil Clin, Fac Hlth, Skive, Denmark
[4] Aarhus Univ, Resenvej 25, DK-7800 Skive, Denmark