title: Resumption of mitosis in frozen-thawed embryos is not related to the chromosomal constitution.
abstract: OBJECTIVE
  To study the relation between the resumption of mitosis after thaw and chromosomal constitution in frozen-thawed embryos. In addition, to evaluate the correlation among the three parameters of resumption of mitosis after thaw, postthaw blastomere loss, and multinucleation.
  
  
  METHODS
  Frozen-thawed embryos were morphologically evaluated at thaw and after 24 hours of culture. Then, fluorescence in situ hybridization (FISH) analysis, including enumeration of 13 chromosomes, was performed by using a combination of peptide nucleic acid and DNA probes.
  
  
  METHODS
  In vitro fertilization laboratory.
  
  
  METHODS
  Forty IVF and/or intracytoplasmic sperm injection patients.
  
  
  METHODS
  Embryo thawing, morphological evaluation, and fluorescence in situ hybridization analysis for aneuploidy screening.
  
  
  METHODS
  Resumption of mitosis, blastomere loss, multinucleation, and chromosome enumeration.
  
  
  RESULTS
  No difference was observed in the chromosomal constitution of embryos with and without resumption of mitosis. Neither was the postthaw blastomere loss connected to the chromosomal constitution. The resumption of mitosis was not associated with postthaw loss of blastomeres or with multinuclearity.
  
  
  CONCLUSIONS
  Resumption of mitosis and blastomere loss of frozen-thawed embryos is not related to chromosome aberrations in the embryo. Further, the resumption of mitosis is not correlated with multinucleation. However, the high incidence of multinucleated embryos after thawing indicates that the freezing and thawing procedure may affect this condition.
authors: The Fertility Clinic, Braedstrup Hospital, Braedstrup, Denmark. inge.e.agerholm@horsens.rm.dk
authors: Inge E
authors: IE
authors: Agerholm
authors: Steen
authors: S
authors: Kølvraa
authors: Dorthe G
authors: DG
authors: Crüger
authors: Charlotte
authors: C
authors: Berg
authors: Gert
authors: G
authors: Bruun-Petersen
authors: Søren
authors: S
authors: Ziebe
mesh_terms: D000328:Adult; D001757:Blastomeres / Q000473:pathology*; D002470:Cell Survival; D002877:Chromosomes, Human; D015925:Cryopreservation; D046149:Embryo Culture Techniques; D020964:Embryo Loss; D004622:Embryo, Mammalian / Q000473:pathology*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008938:Mitosis / Q000235:genetics; D011003:Ploidies; D020554:Sperm Injections, Intracytoplasmic