1. Department of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan, USA
2. National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
3. Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
4. Vincent Memorial Obstetrics and Gynecology Service, Andrology Laboratory and In Vitro Fertilization Unit, Massachusetts General Hospital, Boston, Massachusetts, USA