- Correspondence to Dr Zhengyu Li, Gynecology and Obsterics, Sichuan University West China Second University Hospital, Chengdu 610041, China;
- Received February 27, 2020
- Revision received May 29, 2020
- Accepted June 1, 2020
- First published June 22, 2020.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.