Article History
Received: 2 July 2020
Accepted: 6 August 2020
First Online: 25 August 2020
Compliance with Ethical Standards
:
: The authors declare that they have no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee at Dongguan Maternal and Child Health Care Hospital and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Written informed consent was obtained from the family.