[1] Peking Univ, Dept Obstet & Gynecol, Ctr Reprod Med, Hosp 3, 49 North HuaYuan Rd, Beijing 100191, Peoples R China
[2] Natl Clin Res Ctr Obstet & Gynecol, Beijing 100191, Peoples R China
[3] Beijing Key Lab Reprod Endocrinol & Assisted Repr, Beijing 100191, Peoples R China
[4] Minist Educ, Key Lab Assisted Reprod, Beijing 100191, Peoples R China
[5] Peking Univ, Peking Tsinghua Ctr Life Sci, Beijing 100871, Peoples R China