Received: 10 June 2020
Accepted: 11 October 2020
First Online: 17 October 2020
Ethics approval and consent to participate
: Ethical approval from the Institutional Review Board of Guangzhou Women and Children’s Medical Center and written parental consent were obtained. The research was conducted in compliance with the World Medical Association Declaration of Helsinki.
: Not Applicable.
: The authors declare that they have no competing interests.