Funding for this research was provided by:
Guangzhou Institute of Paediatrics/Guangzhou Women and Children’s Medical Centre (140 000)
Received: 30 April 2020
Accepted: 10 September 2020
First Online: 19 September 2020
Ethics approval and consent to participate
: In our current retrospective analysis, the ethics committee of the GZ Women and Children’s Medical Centre (4AE4237E-7889-4275-95E5-8F469A5C9188) granted the permissions which were required to access and use the medical records. (Found in Additional file InternalRef removed).
: Not applicable.
: The authors declare that they have no competing interests.