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Article History

Received: 18 January 2025

Accepted: 26 March 2026

First Online: 29 March 2026

Declarations

:

: All procedures involving human participants adhered strictly to the ethical standards set forth by the relevant institutional and/or national research committees, in accordance with the principles outlined in the 1964 Helsinki Declaration and its subsequent amendments, or equivalent ethical guidelines. The study protocol was approved by the Medical Ethics Committee of Tangshan Maternal and Children Health Hospital (Approval No. 2023-082-01), which also waived the requirement for informed consent due to the retrospective nature of the study and the use of fully anonymized medical records.

: Not applicable.

: The authors declare no competing interests.