1 Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University (Wu, Zhang, and Drs. Xu and Zhong); Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education (Wu, Zhang, and Drs. Xu and Zhong), Chengdu, Sichuan, China.
2 Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University (Wu, Zhang, and Drs. Xu and Zhong); Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education (Wu, Zhang, and Drs. Xu and Zhong), Chengdu, Sichuan, China. Electronic address: [email protected].