Conclusion
Our findings suggest that pregnant women with a history of HA treatment of IUAs, especially those with a history of repeat HAs, are at higher risk of some adverse obstetric outcomes, and thus, close monitoring of pregnancies of those women is essential to screen for potential pregnancy complications or adverse birth outcomes and implement early prevention and intervention.
Author contributions: W.H. contributed acquisition, statistical analysis and interpretation of the data, and manuscript writing. Z.P.W contributed to data analysis and manuscript writing. B.Y.W. contributed to data analysis. L.L. contributed to the conception, design and supervision of the study. X.C.L. is the guarantor of this study and had full access to all data and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Declaration of Interests: The authors declare that there is no duality of interest associated with this manuscript.
Funding: This study was supported by the Natural Science Foundation of Shanghai (20ZR1444000).