Zhao, Yun
Zou, Li
Xiao, Mei
Tang, Wan
Niu, Hai-yi
Qiao, Fu-yuan
Funding for this research was provided by:
Natural Science Foundation of Hubei Province (2009cda064, 2011cdc098)
health and family planning commission of Hubei province (WJ2015MB121)
Article History
Received: 29 December 2017
Accepted: 25 June 2018
First Online: 3 July 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of Maternal and Child Health Hospital of Hubei Province(201301) and all included women signed written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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