Related Experiment Video
Updated: Aug 13, 2026
10:59
Human Blastocyst Biopsy and Vitrification
Published on: July 26, 2019
Risk factors associated with meiotic errors in blastocysts with mosaic results on biopsy
Jialiu Liu1,2,3, Bing Cai1,2,3, Yan Xu1,2,3
1Reproductive Medicine Center, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.
Human Reproduction Open
|August 12, 2026
Summary
Meiotic errors are rare in mosaic blastocysts, occurring in 3.9% of cases. Risk factors include high-level mosaicism, maternal origin, and advanced maternal age, guiding PGT-AO recommendations.
Area of Science:
- Reproductive medicine
- Genetics
- Embryology
Background:
- Chromosomal mosaicism in blastocysts typically results from postzygotic mitotic errors.
- Preimplantation genetic testing for aneuploidy origin (PGT-AO) can differentiate meiotic from mitotic errors.
- The clinical utility of PGT-AO for mosaic embryos requires further investigation.
Purpose of the Study:
- To identify risk factors for meiotic errors in blastocysts with mosaic biopsy results.
- To evaluate the clinical outcomes of transferring mosaic embryos with mitotic errors.
- To assess the accuracy of PGT-AO in detecting mosaicism.
Main Methods:
- Retrospective analysis of 391 mosaic blastocysts using PGT-AO and SNP arrays.
- Prospective comparison of mosaic embryo transfers (METs) with euploid embryo transfers.
- Single-cell DNA sequencing of donated blastocysts to validate mosaicism detection.
Main Results:
- A low overall meiotic error rate of 3.9% was observed in mosaic blastocysts.
- Meiotic errors were significantly associated with high-level mosaicism (7.2%), maternal origin (8.9%), and advanced maternal age (9.6%).
- Live birth/ongoing pregnancy rates were comparable between METs and euploid embryo transfers.
Conclusions:
- PGT-AO reveals a low prevalence of meiotic errors in mosaic blastocysts.
- PGT-AO is recommended for embryos from patients of advanced maternal age, with high-level mosaicism, or maternal-origin mosaicism.
- Further research is needed to refine PGT-AO accuracy and address limitations in sample size and validation.
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