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Article History

Received: 25 January 2026

Accepted: 18 May 2026

First Online: 4 June 2026

Declarations

:

: This retrospective study was conducted in accordance with the principles of the Declaration of Helsinki. The study protocol was approved by the Human Ethics Committee of Shijiazhuang Maternal and Child Health Care Hospital (Ethics Approval Number: 202316). Given the retrospective nature of the study and the use of de-identified clinical data, the requirement for informed consent was waived by the ethics committee.

: Not applicable

: The authors declare no competing interests.