[1] Fudan Univ, Inst Obstet & Gynecol, Obstet & Gynecol Hosp, Dept Clin Epidemiol, Shanghai, Peoples R China
[2] Zhejiang Univ, Womens Hosp, Key Lab Womens Reprod Hlth Zhejiang Prov,Sch Med, Key Lab Reprod Genet,Minist Educ,Dept Reprod Endo, Hangzhou, Zhejiang, Peoples R China
[3] Shanghai Jiao Tong Univ, Xinhua Hosp, Sch Med, Minist Educ,Shanghai Key Lab Childrens Environm H, Shanghai, Peoples R China
[4] Zhejiang Univ, Womens Hosp, Key Lab Womens Reprod Hlth Zhejiang Prov, Sch Med, Hangzhou, Zhejiang, Peoples R China
[5] Guilin Med Sch, Sch Publ Hlth, Guilin, Guangxi, Peoples R China