1. The Center for Male Reproductive Medicine and Microsurgery, Department of Urology and Cornell Institute for Reproductive Medicine, New York, New York
2. The Population Council, Center for Biomedical Research, New York, New York
3. Department of Public Health, Weill Cornell Medical College, New York, New York
4. Department of Obstetrics and Gynecology, Division of Immunology, Weill Cornell Medical College, New York, New York