Funding for this research was provided by:
jiangsu provincial key discipline of maternal and child health (2017103033)
Article History
Received: 14 June 2021
Accepted: 29 June 2021
First Online: 8 July 2021
Declarations
:
: This study was approved by the ethics committee of Xuzhou Medical University Affiliated Hospital. All patients signed a written informed consent form.
: Not applicable.
: The authors declare that they have no competing interests.