1. Department of Clinical Science, University of Bergen, 5021 Bergen, Norway
2. Tartu University Andrology Centre, 50406 Tartu, Estonia
3. Research Unit for Environment, Occupation and Health, Danish Ramazzini Centre, Aarhus University, 8000 Aarhus, Denmark
4. Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
5. Primary Health Care of the Capital Area, 103 Reykjavik, Iceland
6. Department of Occupational Medicine, Haukeland University Hospital, 5021 Bergen, Norway
7. Department of Gynecology and Obstetrics, Haukeland University Hospital, 5021 Bergen, Norway