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Article History

Received: 19 January 2026

Accepted: 30 March 2026

First Online: 3 April 2026

Declarations

:

: The study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Inner Mongolia Autonomous Region Maternal and Child Health Hospital’s Institutional Review Board (IRB approval number: 2025016-1). As this was a retrospective study, the Ethics Committee approved a waiver of informed consent.

: Not applicable.

: The authors declare no competing interests.