1. Department of Obstetrics and Gynecology, Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
2. Department of Obstetrics and Gynecology, Nanjing Drum Tower Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Graduate School of Peking Union Medical College, Nanjing 210008, China
3. Department of Obstetrics and Gynecology, The First Affiliated Hospital of Xiamen University, Xiamen University, Xiamen 361026, China
4. Fujian Provincial Key Laboratory of Reproductive Health Research, School of Medicine, Xiamen University, Xiamen 361102, China
5. Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China