title: Preimplantation aneuploid embryos undergo self-correction in correlation with their developmental potential.
abstract: OBJECTIVE
  To investigate the incidence of embryos' self-correction during preimplantation development in terms of mosaicism and in correlation with its developmental stage.
  
  
  METHODS
  Prospective study to compare the chromosome status of embryos on day 3 with that of day 5, in correlation with their developmental stage.
  
  
  METHODS
  In vitro fertilization unit of a university-affiliated hospital.
  
  
  METHODS
  Eighty-three aneuploid embryos.
  
  
  METHODS
  Fluorescence in situ hybridization (FISH) reanalysis.
  
  
  METHODS
  Day 3 embryos classified as mosaic or chromosomally abnormal by preimplantation genetic screening (PGS) were reanalyzed on day 5. The results were evaluated in correlation with the embryos' developmental stage.
  
  
  RESULTS
  Out of 83 day 3 aneuploid embryos, 15 (18.1%) were diagnosed with mosaicism. The FISH reanalysis on day 5 demonstrated that 27 embryos (32.6%) were partly or entirely normal disomic. Of these 83 aneuploid embryos, 8 (9.7%) underwent complete self-correction. The PGS results demonstrated that 26.5% of the embryos were trisomic, of which 41.0% underwent trisomic rescue by day 5. Self-correction was in correlation with the embryo's developmental stage, i.e., 38.1% of aneuploid embryos that developed to the blastocyst stage underwent self-correction compared with only 12.5% of embryos that only cleaved after biopsy.
  
  
  CONCLUSIONS
  Our results demonstrate that self-correction of aneuploid and mosaic embryos occurs probably more significantly during development toward the blastocyst stage than in delayed embryos. In addition, trisomic embryos correct themselves more than other aneuploidies. These findings suggest that PGS results must be interpreted with caution.
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Shiri
authors.initials: S
authors.lastname: Barbash-Hazan
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Tsvia
authors.initials: T
authors.lastname: Frumkin
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Mira
authors.initials: M
authors.lastname: Malcov
authors.affiliation: Prenatal Diagnosis Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Yuval
authors.initials: Y
authors.lastname: Yaron
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Tania
authors.initials: T
authors.lastname: Cohen
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Foad
authors.initials: F
authors.lastname: Azem
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ami
authors.initials: A
authors.lastname: Amit
authors.affiliation: Racine IVF Unit, Genetic Institute, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. Electronic address: dalitb@tasmc.health.gov.il.
authors.forename: Dalit
authors.initials: D
authors.lastname: Ben-Yosef
mesh_terms: D000328:Adult; D000782:Aneuploidy; D001706:Biopsy; D001755:Blastocyst / Q000473:pathology / Q000502:physiology*; D020732:Cytogenetic Analysis / Q000379:methods; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D005820:Genetic Testing / Q000379:methods; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D011247:Pregnancy; D019836:Preimplantation Diagnosis; D011379:Prognosis; D011446:Prospective Studies