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Controversies in ART: can the IVF laboratory influence preimplantation embryo aneuploidy?

      Abstract

      Published reports have indicated that rates of preimplantation embryo aneuploidy in a control donor population may vary between IVF centres. This suggests that location-specific conditions, in the clinic, IVF or genetics laboratory, may be influencing the chromosome dynamics or diagnosis. More recent reports suggest that rates of embryo mosaicism, representing mitotic errors, may vary between IVF centres. This would suggest perhaps a laboratory-controlled variable is influencing mitotic cell division during preimplantation embryo development. Various IVF laboratory-controlled factors may be impacting chromosome separation and segregation. Variables including type of culture media, pH, temperature, osmolality and oxygen concentration could all be possible factors influencing embryo aneuploidy. Furthermore, laboratory techniques, method of insemination, laser use or handling of biopsied cells may also influence genetic results. These IVF laboratory variables will be reviewed and literature suggesting a possible link to mitotic aneuploidy/mosaicism discussed.

      Keywords

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      Biography

      Jason E. Swain PhD, HCLD, is the Corporate Laboratory Director of the CCRM IVF Laboratory Network. He completed his BSc at Hillsdale College, his MSc at Purdue University and his PhD at the University of Michigan. His primary research interests include the pursuit of methods to improve in-vitro embryo culture conditions.
      Key message
      As reported, rates of embryo aneuploidy vary between IVF centres. Attention has focused on possible stressors in the IVF laboratory that may influence chromosome separation and segregation. Differences in blastocyst mosaicism rates could indicate laboratory causes of chromosomal errors. Possible mitotic stressors include pH, osmolality, temperature, oxygen tension and culture media.