Article History
Received: 2 August 2020
Accepted: 11 January 2021
First Online: 27 January 2021
Ethics approval and consent to participate
: After approval by the ethics committee of Obstetrics and Gynaecology Hospital of Fudan University. The committee’s reference number is 2018–05.We herein confirm written consent obtained from each patient in accordance with the Declaration of Helsinki in order to report and publish the individual patient data obtained. A written consent to participate from each patient in the current study was obtained.
: Not applicable.
: The authors declare that they have no competing interests.