[1] Acad Med Ctr, Dept Obstet & Gynaecol, NL-1100 DD Amsterdam, Netherlands
[2] Univ Groningen, Univ Med Ctr Groningen, Groningen, Netherlands
[3] Onze Lieve Vrouw Hosp, Amsterdam, Netherlands
[4] Hosp Rijnstate, Arnhem, Netherlands
[5] Scheper Hosp, Emmen, Netherlands
[6] Leiden Univ, Med Ctr, Leiden, Netherlands
[7] Twee Steden Hosp, Tilburg, Netherlands
[8] Sint Elisabeth Hosp, Tilburg, Netherlands
[9] Med Ctr Haaglanden, The Hague, Netherlands
[10] Gelre Hosp, Apeldoorn, Netherlands
[11] Univ Med Ctr, Utrecht, Netherlands
[12] Martini Hosp, Groningen, Netherlands
[13] Spaarne Hosp, Hoofddorp, Netherlands
[14] Amphia Hosp, Breda, Netherlands
[15] Atrium Med Ctr, Heerlen, Netherlands
[16] Univ Med Ctr, Nijmegen, Netherlands
[17] Deventer Hosp, Deventer, Netherlands
[18] Univ Hosp, Maastricht, Netherlands
[19] Maxima Med Ctr, Veldhoven, Netherlands