Wang, Wei
Liu, Hong
Li, Jing
Wei, Daimin
Zhang, Jiangtao
Wang, Jianfeng
Ma, Jinlong
Shi, Yuhua
Chen, Zi-Jiang
Article History
Received: 28 May 2018
Accepted: 17 December 2018
First Online: 15 January 2019
Ethics approval and consent to participate
: The study had been approved by the ethics committee of the Reproductive Medical Center of Shandong University, and the institutional review boards in other study sites permitted the use of the approval document of the ethics committee of the Reproductive Medical Center of Shandong University. All patients provided written informed consent prior to participation. Ethics approval has been sought from the ethics committee at the Reproductive Medical Center affiliated with Shandong University (2015 IRB approval no. 20). Written informed consent is obtained from each couple before screening.
: Not applicable.
: The authors declare that they have no competing interests.
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