1 Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, Guangdong, China.
2 Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong, China.
3 Department of Obstetrics and Gynecology, Guangzhou Huadu District Maternal and Child Health Hospital, Guangzhou 510800, Guangdong, China.
4 Department of Obstetrics and Gynecology, The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Guangzhou 511500, Guangdong, China.
5 Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hunan, China.
6 Department of Obstetrics and Gynecology, Key Laboratory for Major Obstetric Diseases of Guangdong Province, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, Guangdong, China;Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou 510150, Guangdong, China.