Wang, Ting
Zhang, Xiaodan
Lu, Zhiying
Wang, Junyan
Hua, Keqin
Article History
Received: 12 September 2018
Accepted: 22 January 2019
First Online: 30 January 2019
Ethics approval and consent to participate
: Ethics approval was obtained from the Ethics Committee of the Department of gynaecology and obstetrics affiliated to Fudan University.
: Not applicable.
: The authors declare that they have no competing interests.
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