Chizuru Misago*1, Kenji Takehara*2, Takashi Okai*3, Ritsuko Toda*4, Hirokatsu Kitai*5, Kimikazu Hayashi*6, Mariko Shibata*7, Toshiyuki Ojima*8, Eiko Asou*8, Yoshikazu Nakamura*8
*1Faculty of Liberal Arts, Tsuda College, Department of Epidemiology, National Institute of Public Health, *2University of Tsukuba Graduate School of Comprehensive Human Sciences Department of Epidemiology, National Institute of Public Health, *3Department of Obstetrics & Gynecology, Shows University School of Medicine, *4Japan Association for Childbirth Education, *5Department of Obstetrics & Gynecology, Saitama Social Insurance Hospital, *6Department of Obstetrics & Gynecology, Kanmon Medical Center, *7Department of Nursing, Jobu University, *8Department of Public Health, Jichi Medical School
Japanese Journal of Maternal Health 47(2): 448-454, 2006.