[1] Erasmus Univ, Med Ctr, Obstet & Gynaecol, Rotterdam, Netherlands
[2] Leiden Univ, Med Ctr, Obstet & Gynaecol, Leiden, Netherlands
[3] Univ Amsterdam, Acad Med Ctr, Obstet & Gynaecol, NL-1105 AZ Amsterdam, Netherlands
[4] Univ Groningen, Univ Med Ctr Groningen, Obstet & Gynaecol, Groningen, Netherlands
[5] Radboudumc, Obstet & Gynaecol, Nijmegen, Netherlands