SAKURAI Rina, KIDO Koichiro, NISHIZAWA Miki, SETO Michiharu, MORITA Masayoshi, NAMAI Shigenari, HIRAIKE Haruko, MATSUMOTO Yasuhiro, RYO Eiji, AYABE Takuya (Department of Obstetrics & Gynecology, Teikyo University, School of Medicine)

TANAKA Toshitaka, ITO Saki, KOBAYASHI Toru, MATSUZAWA Nana, MURASE Yoshiko, TANAKA Satomi, YATA Shotaro, KANEDA Hiroshi, MITSUHASHI Naoki (Obstetrics and Gynecology, Juntendo University Shizuoka Hospital)

NITTA Emiko, TOMOYA Yamashita, ITO Megumi, ABOELLAIL Mohamed, MORI Nobuhiro, HANAOKA Uiko, KANENISHI Kenji, TANAKA Hirokazu, HATA Toshiyuki (Department of Perinatology and Gynecology, Kagawa University Graduate School of Medicine)

SAKUMA Junya^{1, 2}, TAKANO Mayumi^{1, 3}, HAYASHI Rika^{1, 3}, NAGASAKI Sumito^{1, 3}, OOJI Ayako³, HAYATA Eijirou³, MAEMURA Toshimitsu³, NAKATA Masahiko^{1, 3}, MORITA Mineto^{1, 3} (1.Department of Obstetrics and Gynecology, Toho University Graduated School, 2.Characteristic Findings by Ultrasonic Examination in Cases of Secondary Postpartum Hemorrhage Obstetrics and Gynecology, Omori Red Cross Hospital, 3.Department of Obstetrics and Gynecology, Toho University Omori Medical)

MATSUKI Atsushi, NAKAMURA Hiroaki, NAGATSUJI Makiko, INOUE Motoi, KOMATSU Maya, MATSUKI Takako, NISIMOTO Sachiyo, KATAYAMA Hiroko, TAHARA Mie, NAKAMOTO Osamu (Obstetrics, Osaka City General Hospital)