Let the data do the talking: the need to consider mosaicism during embryo selection

Area of Science:

• Reproductive Medicine
• Genetics
• Embryology

Background:

• Chromosomal mosaicism, the presence of cells with varying chromosome numbers, has been observed in human embryos for 30 years.
• Early preimplantation genetic testing for aneuploidy (PGT-A) methods could not accurately detect mosaicism, leading to potential misdiagnoses.
• Modern PGT-A techniques analyze multicellular biopsies, enabling the identification of mosaicism and intermediate chromosomal copy number variations.

Purpose of the Study:

• To discuss the clinical implications of chromosomal mosaicism detected by modern PGT-A.
• To highlight the association between specific mosaicism features and variable clinical outcomes.
• To advocate for the integration of mosaicism assessment into clinical embryo selection strategies.

Main Methods:

• Review of recent data on chromosomal mosaicism detected through preimplantation genetic testing for aneuploidy (PGT-A).
• Analysis of the relationship between specific mosaicism characteristics and clinical outcomes.
• Discussion of the diagnostic capabilities of modern PGT-A techniques in identifying mosaic embryos.

Main Results:

• Modern PGT-A can accurately identify chromosomal mosaicism in human embryos.
• Specific features of detected mosaicism are linked to diverse clinical outcomes.
• The accurate diagnosis of mosaicism is crucial for effective clinical management.

Conclusions:

• Chromosomal mosaicism is a significant factor influencing clinical outcomes in assisted reproductive technologies.
• Considering mosaicism in embryo selection can lead to more informed clinical decisions.
• Further research and clinical integration of mosaicism data are essential for optimizing embryo selection and improving success rates.