1 Department of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, Nagoya 466-4660, Japan; Division of Reproduction and Perinatology, Center for Maternal-Neonatal Care, Nagoya University Hospital, Nagoya, Japan. Electronic address: itoto@med.nagoya-u.ac.jp.
2 Department of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, Nagoya 466-4660, Japan.