1. Centre for Reproductive Medicine, Academic Medical Centre, Meiberg dreef 9, 1105 AZ, Amsterdam, The Netherlands
2. Department of Obstetrics and Gynaecology, Máxima Medical Centre, Postbus 7777, 5500 MB, Veldhoven, The Netherlands
3. Department of Obstetrics and Gynaecology, OLVG oost, Oosterpark 9, 1091 AC, Amsterdam, The Netherlands
4. Jeroen Bosch Hospital, Department of Obstetrics and Gynecology, Postbus 90153, 5200 ME, 's-Hertogenbosch, The Netherlands
5. Fertility Clinic Twente, Demmersweg 66, 7556 BN, Hengelo, The Netherlands
6. Department of Obstetrics and Gynaecology, Sint Franciscus Gasthuis, Kleiweg 500, 3045 PM, Rotterdam, The Netherlands
7. Department of Obstetrics and Gynecology, Isala Hospital, Postbus 10400, 8000 GK, Zwolle, The Netherlands
8. Department of Obstetrics and Gynaecology, Canisius Wilhelmina Hospital, Postbus 9015, 6500 GS, Nijmegen, The Netherlands
9. Centre for Reproductive Medicine, Radboud University Medical Centre, Geert Grooteplein Zuid 10, 6525 GA, Nijmegen, The Netherlands
10. Department of Obstetrics and Gynaecology, Spaarne Gasthuis, Postbus 417, 2000 AK, Haarlem, The Netherlands
11. Department of Obstetrics and Gynaecology, St. Antonius hospital Nieuwegein, Koekoekslaan 1, 3435 CM, Nieuwegein, The Netherlands
12. Department of Obstetrics and Gynaecology Amphia, Postbus 90157, 4800 RL, Breda, The Netherlands
13. Centre for Reproductive Medicine, University Medical Centre Utrecht, Postbus 85500, 3508 GA, Utrecht, The Netherlands
14. Monash University, Monash Medical Centre, 246 Clayton Rd, Clayton VIC 3168, Australia
15. Department of Obstetrics and Gynaecology, Martini Hospital, Groningen
16. Department of Obstetrics and Gynaecology, Leiden University Medical Centre, Leiden
17. Department of Obstetrics and Gynaecology Groene Hart Hospital, Gouda
18. Department of Obstetrics and Gynaecology Noord West Groep Alkmaar, Alkmaar
19. Department of Obstetrics and Gynaecology MC Zuiderzee, Lelystad
20. Department of Obstetrics and Gynaecology Scheper Hospital, Emmen
21. Department of Obstetrics and Gynaecology Amphia, Breda
22. Department of Obstetrics and Gynaecology Medical Centre Leeuwarden, Leeuwarden
23. Department of Obstetrics and Gynaecology, Spaarne Hospital, Hoofddorp
24. Department of Obstetrics and Gynaecology Wilhelmina Hospital, Assen