* Correspondence:
Shixuan Wang, PhD, Department of Obstetrics and Gynaecology, Tongji
Hospital, Tongji Medical College, Huazhong University of Science and
Technology, Wuhan 430022, China. Email:sxwang@tjh.tjmu.edu.cn.
Telephone number: +86-139-9555-3319. Fax number: 86-27-83663087
Meng Wu, PhD, Department of Obstetrics and Gynaecology, Tongji Hospital,
Tongji Medical College, Huazhong University of Science and Technology,
Wuhan 430022, China.
Email:mengwu@tjh.tjmu.edu.cn.
Telephone number: +86-159-2712-2310. Fax number: 86-27-83662407
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