[1] Vrije Univ Amsterdam, Med Ctr, Dept Reprod Med, Postal Code 7057, NL-1007 MB Amsterdam, Netherlands
[2] Sint Franciscus Hosp, Dept Obstet & Gynaecol, Kleiweg 500, NL-3045 PM Rotterdam, Netherlands
[3] Jeroen Bosch Hosp, Dept Obstet & Gynaecol, Henri Dunantstr 1, NL-5223 GZ Den Bosch, Netherlands
[4] OLVG Oost, Dept Obstet & Gynaecol, Oosterpk 9, NL-1091 AC Amsterdam, Netherlands
[5] Acad Med Ctr, Dept Obstet & Gynaecol, Ctr Reprod Med, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands
[6] Flevo Hosp, Dept Obstet & Gynaecol, Hosp Weg 1, NL-1315 RA Almere, Netherlands
[7] Gelre Hosp, Dept Obstet & Gynaecol, Albert Schweitzerlaan,31, NL-7334 DZ Apeldoorn, Netherlands
[8] Rivierenland Hosp, Dept Obstet & Gynaecol, President Kennedylaan 1, NL-4002 WP Tiel, Netherlands
[9] Diakonessen Hosp, Dept Obstet & Gynaecol, Bosboomstr 1, NL-3582 KE Utrecht, Netherlands
[10] Spaarne Gasthuis, Dept Obstet & Gynaecol, Boerhaavelaan 22, NL-2035 RC Haarlem, Netherlands
[11] Tergooi Hosp, Dept Obstet & Gynaecol, Rijksstraatweg 1, NL-1261 AN Blaricum, Netherlands
[12] Amstelland Hosp, Dept Obstet & Gynaecol, Laan Helende Meesters 8, NL-1186 AM Amstelveen, Netherlands
[13] Zaans Med Ctr, Dept Obstet & Gynaecol, Julianapl 58, NL-1502 DV Zaandam, Netherlands
[14] Martini Hosp Groningen, Dept Obstet & Gynaecol, Swietenpl 1, NL-9700 RB Groningen, Netherlands
[15] Zuyderland Med Ctr, Dept Obstet & Gynaecol, Henri Dunantstr 5, NL-6419 PC Heerlen, Netherlands
[16] Refaja Hosp, Dept Obstet & Gynaecol, Boerhaavestr 1, NL-9501 HE Stadskanaal, Netherlands
[17] OLVG, Dept Obstet & Gynaecol, West,Jan Tooropstr, NL-1061 AE Amsterdam, Netherlands
[18] Ikazia Med Ctr, Dept Obstet & Gynaecol, Montessoriweg 1, NL-3083 AN Rotterdam, Netherlands
[19] IJsselland Hosp, Dept Obstet & Gynaecol, Prins Constantijnweg 2, NL-2906 ZC Capelle aan den IJssel, Netherlands
[20] Gelre Hosp, Dept Obstet & Gynaecol, Elterweg 77, NL-7207 AE Zutphen, Netherlands
[21] Univ Med Ctr Utrecht, Dept Reprod Med & Gynaecol, Heidelberglaan 100, NL-3584 CX Utrecht, Netherlands
[22] Maastricht Univ, Med Ctr, Dept Reprod Med, P debeylaan,25, NL-6229 HX Maastricht, Netherlands
[23] Deventer Hosp, Dept Obstet & Gynaecol, Nico Bolkesteinlaan 75, NL-7416 SE Deventer, Netherlands
[24] St Antonius Hosp, Dept Obstet & Gynaecol, Koekoekslaan 1, NL-3435 CM Nieuwegein, Netherlands
[25] Westfriesgasthuis, Dept Obstet & Gynaecol, Maelsonstr 3, NL-1624 NP Hoorn, Netherlands
[26] Acad Med Ctr, Dept Epidemiol Biostat & Bioinformat, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands
[27] Acad Med Ctr, Dept Radiol & Nucl Med, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands
[28] Robinson Res Inst, Sch Paediat & Reprod Hlth, Adelaide, SA, Australia
[29] South Australian Hlth & Med Res Inst, Adelaide, SA, Australia