1. Department of Reproductive Medicine and Gynaecology (M.D., F.J.M.B.), 3508 GA Utrecht, The Netherlands;
2. Julius Center for Health Sciences and Primary Care (M.D., M.J.C.E., Y.T.v.d.S.), University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands;
3. National Institute for Public Health and the Environment (W.M.M.V., M.E.T.D., E.H.J.M.J.), 3720 BA Bilthoven, The Netherlands