Funding for this research was provided by:
Zhejiang Provincial Natural Science Foundation of China (LY18H160004)
the Medical and Health Science and Technology Plan Project of Zhejiang Province (2015KYA124)
the National Natural Science Foundation of China (81202066, 81672568)
Received: 25 April 2018
Accepted: 31 October 2018
First Online: 16 November 2018
Ethics approval and consent to participate
: The present study was approved by the Institutional Review Board, Women’s hospital, School of Medicine, Zhejiang University. Written, informed consent has been given and obtained from all individual participants included in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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