Corresponding author
Chieko Kurimoto
Department of Obsterics, Funabashi Central Hospital
6-13-10, Kaijin, Funabashi-shi, Chiba 273-8556, Japan
E-mail: ckurimoto06@yahoo.co.jp
Telephone number: +81-47-433-2111, FAX number: +81-47-435-2655