1. Department of Gynecology, Osaka International Cancer Institute, Osaka 540-0008, Japan
2. Department of Obstetrics and Gynecology, Graduate School of Medicine, Osaka University, Osaka 565-0871, Japan
3. Department of Obstetrics and Gynecology, Osaka General Medical Center, Osaka 558-8558, Japan
4. Department of Forensic Medicine, School of Medicine, Kindai University, Osaka 577-8502, Japan