In the published article, there was an error in the Affiliation. Instead of “Department of Obstetrics and Gynecology, Jiao Tong University School of Medicine, Shanghai, China,” it should be “Department of Obstetrics and Gynecology, Shanghai General Hospital, Shanghai, China.”
Additionally, a correction has been made to Methods section, paragraph 1. The last sentence previously stated “This research was registered with the Chinese Clinical Trial Registry (ChiCTR2000036575).” However the correct sentence is “This research was funded by the Chinese Clinical Trial Registry (ChiCTR2000036575).” The Conflict of Interest statement has also been updated to reflect this.
The authors apologize for these errors and state that they do not change the scientific conclusions of the article in any way. The original article has been updated.
Conflict of interest
This study received funding from Chinese Clinical Trial Registry (ChiCTR2000036575). The funder had the following involvement with the study: service charge of postgraduates collecting data and also for publishing fee.
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