1. Department of Endocrinology, University Medical Centre Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
2. Department of Obstetrics and Gynaecology, University Medical Centre Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
3. Department of Endocrinology, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
4. Department of Obstetrics and Gynaecology, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
5. Division of Medical Biology, University Medical Centre Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
6. Department of Internal Medicine, Academic Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
7. Department of Internal Medicine, Erasmus Medical Centre, ’s-Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
8. Department of Internal Medicine, Medical Centre Haaglanden, Lijnbaan 32, 2512 VA The Hague, The Netherlands
9. Department of Endocrinology, Atrium Medical Centre, Henri Dunantstraat 5, 6419 PC Heerlen, The Netherlands
10. Department of Endocrinology, Meander Medical Centre, Ringweg Randenbroek 110, 3816 CP Amersfoort, The Netherlands