^○Hiroki Ishibashi, Hidenori Sasa, Hideki Iwahashi, Soichiro Kakimoto, Takahiro Sakamoto, Taira Hada, Jin Suminokura, Morikazu Miyamoto, Rie Suzuki, Masashi Takano (Department of Obstetrics and Gynecology, National Defense Medical College Hospital, Saitama, Japan)

^○Mari Mukai, Nao Arisawa, Kaori Naruse, Rumi Suzuki, Yutaka Inamoto, Tomoaki Kano (Department of Obstetrics and Gynecology, JA Shizuoka Kohseiren Enshu Hospital, Hamamatsu, Japan)

^○Itsuka Kai¹, Toru Kikkawa², Miho Kodama¹, Rikako Nakamae¹, Norio Miharu¹, Kenjiro Date¹ (1.Department of Obstetrics and Gynecology, Hiroshima Red Cross and Atomic Bomb Hospital, Hiroshima, Japan, 2.Department of Palliative care, Hiroshima Red Cross and Atomic Bomb Hospital, Hiroshima, Japan)

^○Jing Wang Lin (Department of Obstetrics and Gynecology, Da Chien General Hospital, Miaoli, Taiwan)

^○Yoshiaki Tsukizawa, Yuki Sakai, Karen Iwama, Naoko Tanaka, Rinko Kubo, Keiji Morikawa, Maiko Ueda, Yosuke Katayama, Shoko Tamada, Sekino Madoka, Masae Yorimitsu, Junichi Kodama (Department of Obstetrics and Gynecology, Hiroshima City Hiroshima Citizens Hospital, Hiroshima, Japan)

^○Shingo Horikawa, Ryusuke Kaya, Reira Masuda, Taro Idei, Satoru Tsuda, Akinobu Izumi, Miki Okubo, Akiko Shimagata, Eri Iikura, Rui Yamamoto, Keiji Morimoto, Kyosuke Yamada, Aikou Okamoto (Department of Obstetrics and Gynecology, The Jikei University School of Medicine, Tokyo, Japan)

^○Sayuri Iwai¹, Atsuko Kiyota¹, Hirokazu Naoi², Mikiko Terada¹, Yuri Kamino¹, Mayu Shiomi¹, Chikako Tsukahara¹, Ayako Hosoi¹, Shinsuke Koyama¹, Yukihiro Nishio¹ (1.Department of Obstetrics and Gynecology, Osaka Police Hospital, Osaka, Japan, 2.Department of Obstetrics and Gynecology, Kumamoto City Hospital, Kumamoto, Japan)

^○Eriko Shiraishi, Akari Shinoda, Yuusuke Mori, Yuuta Kasahara, Takuma Sato, Miwa Hidaka, Atsuko Kusuhara, Hiroshi Kishi, Aikou Okamoto (Department of Obstetrics and Gynecology, The Jikei University School of Medicine, Tokyo, Japan)

^○Satoshi Nishiyama, Sotaro Hayashi, Lifa Lee, Yoko To, Hiroshi Tsujioka (Department of Obstetrica and gynecology, Aso Iizuka Hospital, Fukuoka, Japan)

^○Aki Matsuda, Makiko Hino, Kengo Hatae, Ayano Watanabe, Asako Sera, Naomi Iwasa, Marie Fukutake, Michiko Wada, Yoshihisa Hattori, Takashi Kurahashi (Department of Obstetrics and Gynecology, National Hospital Organization Saitama Hospital, Saitama, Japan)

^○Saya Watanabe¹, Shinya Ohki¹, Tomoko Shimada¹, Yoshikazu Sou¹, Sayaki Shimada¹, Yuuka Tanaka², Kana Ietani², Masataka Adachi¹, Akiko Ohno¹, Hiroshi Yamashita¹ (1.National Hospital Organization Tokyo Medical Center, Japan, 2.Keio University School of Medicine Obstetrics and Gynecology, Japan)