1Department of Neuropsychopharmacology, National Center of Neurology and Psychiatry, 4-1-1, Ogawahigashi, Kodaira, Tokyo, Japan
2Department of Public Health, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo, Tokyo, Japan
3Japan Association of Obstetricians and Gynecologists, 14 Yahatacho, Ichigaya-Hachimanmachi, Shinjuku-ku, Tokyo, 162-0844 Japan
4Department of Obstetrics and Gynecology, Japanese Red Cross Katsushika Maternity Hospital, 5-11-12 Tateishi, Katsushika-ku, Tokyo, 124-0012 Japan
5Department of Obstetrics and Gynecology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8666 Japan
6Department of Pediatrics, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8666 Japan
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