1. Department of Obstetrics and Gynecology, International University of Health and Welfare, Narita, Chiba, Japan
2. Department of Diabetes, Metabolism and Endocrinology, International University of Health and Welfare Hospital, Nasushiobara, Tochigi, Japan
3. Department of Obstetrics and Gynecology, International University of Health and Welfare Hospital, Nasushiobara, Tochigi, Japan