Received: 14 December 2020
Accepted: 8 March 2021
First Online: 20 March 2021
: This study protocol was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee of Guangzhou Women and Children’s Medical Center of Guangzhou Medical University. Written informed consents were signed during hospitalization. The data used in this study was anonymised before its use.
: Not applicable.
: The authors declare that they have no competing interests to disclose.