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Article History

Accepted: 19 May 2023

First Online: 5 June 2023

Declarations

:

: All authors declare to have no conflict of interest.

: The authors assert that all procedures contributing to this work comply with the ethical standards of the relevant national and institutional committees on human experimentation and with the Helsinki Declaration of 1964, as revised in 2008. This study was approved by the Ethics Committee of the National Research Institute for Family Planning, Beijing, China.

: All participants voluntarily participated in the study and signed the informed consent.

: Not applicable.