[1] Peking Univ, Dept Urol, Hosp 3, Beijing 100191, Peoples R China
[2] Peking Univ, Reprod Med Ctr, Hosp 3, Beijing 100191, Peoples R China
[3] First Hosp Nanchang, Dept Obstet & Gynaecol, Nanchang 330008, Peoples R China
[4] Capital Med Univ, Beijing Tongren Hosp, Dept Urol, Beijing 100730, Peoples R China
[5] Fucheng Tech Serv Ctr Family Planning, Fucheng 053700, Hebei, Peoples R China
[6] Tianjin United Family Hosp, Reprod Med Ctr, Tianjin 300221, Peoples R China
[7] Natl Res Inst Family Planning, Dept Male Clin Res, Natl Hlth & Family Planning Key Lab Male Reprod H, Beijing 100081, Peoples R China