Acknowledgements
The authors thank Dr. Xiaohua Liu for help with data validation and statistical assistance. We are very grateful to our volunteer patients for taking part in our research. Without the efforts, this research would not have been possible.
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Figure legends
Figure 1. Flow chart of the patient selection.
Figure 2. Kaplan- Meier curve for time to live birth.
Figure S1.
Birth rate and multiple birth rate in relation to the proportion of eSBT among fresh blastocyst transfers for women over 36 years from 2015 to 2018.
Table 1. Baseline characteristics of the patients at the start of the IVF/ICSI.