[1] Sichuan Univ, Lab Genet Dis & Perinatal Med, Chengdu 610041, Sichuan, Peoples R China
[2] Sichuan Univ, West China Second Univ Hosp, Key Lab Birth Defects & Related Dis Women & Childr, Minist Educ, Chengdu 610041, Sichuan, Peoples R China
[3] Sichuan Univ, West China Sch Nursing, Chengdu 610041, Sichuan, Peoples R China
[4] Sichuan Univ, West China Second Univ Hosp, Dept Obstet & Gynecol, Chengdu 610041, Sichuan, Peoples R China
[5] West China Second Univ Hosp, Sichuan Univ, Key Lab Birth Defects & Related Dis Women & Childr, Minist Educ, Chengdu 610041, Sichuan, Peoples R China