1. Department of Urology, Stanford University School of Medicine, Palo Alto, California
2. Department of Environmental Medicine, Institute of Public Health, University of Southern Denmark, Winsloewsparken, Odense, Denmark
3. Division of Male Reproductive Medicine and Surgery, Scott Department of Urology, Baylor College of Medicine, Houston, Texas
4. University Department of Growth and Reproduction, Rigshospitalet, Copenhagen, Denmark