1. Department of Urology Peking University Third Hospital Beijing China
2. Department of Reproductive Medicine Center Peking University Third Hospital Beijing China
3. Department of Epidemiology Harvard T.H. Chan School of Public Health Boston Massachusetts USA
4. Research Center of Clinical Epidemiology Peking University Third Hospital Beijing China
5. Department of Andrology Third Affiliated Hospital of Zhengzhou University Zhengzhou China
6. Department of Urology Peking University First Hospital Beijing China
7. Institute of Urology Peking University Beijing China