^○Kiyoshi Kanno, Kunitoshi Kinjyo, Kota Sakakibara, Mitsuru Toeda, Senba Satoki, Hirofumi Ochi, Michiru Yasui, Kei Kato, Kyoko Shimada, Yasunori Yoshino, Mari Sawada, Shintaro Sakate, Tomonori Hada, Shiori Yanai, Masaaki Andou (Department of Obstetrics and Gynecology, Kurashiki Medical Center, Okayama Japan)

^○Izumi Kusuki (Department of Obstetrics and Gynecology, Graduate School of Nursing for Health Care Science, Kyoto Prefectural University of Medicine, Japan)

^○Tae-Joong Kim (Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Korea)

^○Mari Kitade, Keisuke Murakami, Yukiko Okada, Shinichiro Ikuma, Rie Ozaki, Yu Kawasaki, Asako Ochiai, Shiori Takeuchi, Yuko Matsumura, Atsuo Itakura (Department of Obstetrics and Gynecology, Juntendo University Faculty of Medicine, Japan)

^○Amphan Chalermchockcharoenkit (Department of Obstetrics and Gynecology, Faculty of Medicine Siriraj Hospital, Mahidol University, Thailand)