[1] Sanno Hosp, Ctr Human Reprod & Gynecol Endoscopy, Tokyo, Japan
[2] Tsukuba Gakuen Hosp, Dept Urol, Ibaraki, Japan
[3] Int Univ Hlth & Welf Hosp, Ctr Infertil & IVF, Otawara, Tochigi, Japan
[4] Int Univ Hlth & Welf Hosp, Dept Urol, Otawara, Tochigi, Japan