1. Department of Endocrinology, Research Institute for Endocrinology, Reproduction and Metabolism; Departments of
2. Internal Medicine and
3. Department of Clinical Chemistry, University Hospital Vrije Universiteit Amsterdam, De Boelelaan 1117, Postbus 7057, 1007 MB Amsterdam, The Netherlands
4. Obstetrics and Gynaecology, Institute for Cardiovascular Research-Vrije Universiteit; and
5. The Gaubius Laboratory, TNO-PG, Postbus 2215, 2301 CE Leiden, The Netherlands