[1] Sungkyunkwan Univ, Sch Med, Samsung Med Ctr, Dept Obstet & Gynecol, Seoul, South Korea
[2] Sungkyunkwan Univ, Sch Med, Samsung Med Ctr, Dept Pathol, Seoul, South Korea
[3] Univ Pittsburgh, Dept Obstet Gynecol & Reprod Sci, Magee Womens Res Inst, Pittsburgh, PA USA