Institution: | (1) Department of Obstetrics and Gynecology, Yamanashi Medical University, Shimokato 1110, Tamaho, Nakakoma, 409-3898 Yamanashi, Japan;(2) Department of Epidemiology and Environmental Health, Juntendo University School of Medicine, Hongo 2-1-1, Bunkyo, 113-0033 Tokyo, Japan |