Chen, Yu
Shi, Xinyan
Wang, Zhiyi
Zhang, Lin
Article History
Received: 9 May 2025
Accepted: 24 October 2025
First Online: 18 November 2025
Declarations
:
: The study was approved by the Ethics Committee of Hangzhou Maternity Protection Hospital (Medical Ethics Review A [152], 2024). As a retrospective study, the study process did not cause additional adverse effects on patients, and patient information and data were adequately protected. The study followed the ethical principles of the Declaration of Helsinki and was conducted in accordance with the "Measures for the Ethical Review of Biomedical Research Involving Human Subjects". The ethics committee granted a waiver of informed consent for the retrospective and anonymized character of the data.
: Not applicable.
: The authors declare no competing interests.