1. Department of Reproductive Medicine and Gynecology (E.A.H.K., M.J.C.E., A.J.G., F.J.M.B., B.C.J.M.F.), University Medical Center, 3584 CX Utrecht, The Netherlands
2. Department of Public Health (M.J.C.E.), Erasmus Medical Center, 3000-CB Rotterdam, The Netherlands
3. Division of Reproductive Medicine (C.B.L.), Department of Obstetrics and Gynecology, Vrije Universiteit Medical Center, 1007 MB Amsterdam, The Netherlands
4. Department of Obstetrics and Gynecology (M.J.K.-B.), Amphia Hospital Langendijk, 4800 RL Breda, The Netherlands
5. Section of Reproductive Medicine (A.H.), Department of Obstetrics and Gynecology, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
6. Department of Obstetrics and Gynecology (C.C.M.B.), University Medical Center St. Radboud, 6500 HB Nijmegen, The Netherlands
7. Division of Reproductive Medicine (J.S.E.L.), Erasmus Medical Center, 3000-CB Rotterdam, The Netherlands
8. Department of Obstetrics and Gynecology, and Department of Internal Medicine (A.P.N.T., F.H.d.J.), Erasmus Medical Center, 3000-CB Rotterdam, The Netherlands