Huang, Jun http://orcid.org/0000-0002-4680-5344
Hu, Hai-Ling
Yan, Zi-Ning
Fan, Li
Rui, Yi-Fei
Shen, Dan
Li, Jie
Article History
Received: 5 September 2018
Accepted: 27 May 2019
First Online: 7 June 2019
Ethics approval and consent to participate
: The study complied with the Declaration of Helsinki and was reviewed and approved by the Human Subjects Committee of Changzhou No. 2 People’s Hospital approved this study. Written informed consent was obtained from each couple enrolled in the study.
: This manuscript does not include any individual person’s data.
: The authors declare that they have no competing interests.