[1] Univ Tokyo, Dept Obstet & Gynecol, Bunkyo Ku, Tokyo 1138655, Japan
[2] Keio Univ, Dept Obstet & Gynecol, Tokyo, Japan
[3] Keio Univ, Dept Radiol, Tokyo, Japan
[4] Juntendo Univ, Dept Radiol, Tokyo, Japan
[5] Sanno Hosp, Reprod Ctr, Tokyo, Japan
[6] Teikyo Univ, Dept Obstet & Gynecol, Mizonokuchi Hosp, Kanagawa, Japan
[7] Teikyo Univ, Dept Radiol, Mizonokuchi Hosp, Kanagawa, Japan
[8] Univ Fukui, Dept Obstet & Gynecol, Fukui 910, Japan