1 Department of Gynecology and Obstetrics (Drs. Sano, Asano, Tanioka, and Shigeta), Yokohama Municipal Citizen's Hospital, Yokohama, Japan.
2 Department of Gynecology and Obstetrics (Drs. Sano, Asano, Tanioka, and Shigeta), Yokohama Municipal Citizen's Hospital, Yokohama, Japan. Electronic address: [email protected].
3 Department of Orthopedics (Dr. Kadowaki), Yokohama Municipal Citizen's Hospital, Yokohama, Japan.