[1] Chungnam Natl Univ Hosp, Dept Obstet & Gynecol, 33 Munhwa Ro, Daejeon 301721, South Korea
[2] Chungnam Natl Univ, Sch Med, Daejeon, South Korea
[3] Natl Canc Ctr, Ctr Uterine Canc, Res Inst & Hosp, Goyang, South Korea
[4] Sungkyunkwan Univ, Kangbuk Samsung Hosp, Total Healthcare Ctr, Sch Med, Seoul, South Korea