[1] Chinese Univ Hong Kong, Dept Obstet & Gynaecol, Prince Wales Hosp, Hong Kong, Peoples R China
[2] Chinese Univ Hong Kong, Dept Paediat, Prince Wales Hosp, Hong Kong, Peoples R China
[3] Chinese Univ Hong Kong, Dept Anat & Cellular Pathol, Prince Wales Hosp, Hong Kong, Peoples R China