Article History
Received: 27 February 2022
Accepted: 14 May 2022
First Online: 6 June 2022
Declarations
:
: The authors declare no conflict of interest.
: The study was approved by the Ethic Committee of Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China. It was performed in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.