title: Preimplantation genetic diagnosis for chromosome rearrangements - one blastomere biopsy versus two blastomere biopsy.
abstract: OBJECTIVE
  Preimplantation Genetic Diagnosis (PGD) has proven to be a useful reproductive option for carriers of some chromosome rearrangements. The data presented in this study compares the impact of one versus two blastomere biopsy on the likelihood of achieving a PGD result, as well as the effect on subsequent embryo development and clinical outcomes.
  
  
  METHODS
  IVF-PGD couples had either one or two blastomeres biopsied from all embryos with ≥7 blastomeres on day 3 post oocyte collection. These blastomeres were assessed for the specific chromosome rearrangement using Fluorescent In-situ Hybridisation (FISH). Further embryo development was monitored on days 4 and 5. Clinical outcomes were assessed retrospectively.
  
  
  RESULTS
  The data shows that statistically more embryos achieved a PGD result following two blastomere biopsy, compared with one blastomere biopsy (92 % versus 88 %, respectively). Furthermore it was found that embryo development and clinical outcomes were similar between the two biopsy groups.
  
  
  CONCLUSIONS
  Based on this analysis it appears that the biopsy of two blastomeres from embryos with ≥7 blastomeres on day 3 is a valid and successful approach for couples presenting for IVF-PGD for a chromosome rearrangement.
authors.affiliation: Monash IVF, 1/252 Clayton Rd, Clayton, VIC, 3168, Australia. dbrodie@monashivf.com
authors.forename: D
authors.initials: D
authors.lastname: Brodie
authors.forename: C E
authors.initials: CE
authors.lastname: Beyer
authors.forename: E
authors.initials: E
authors.lastname: Osborne
authors.forename: V
authors.initials: V
authors.lastname: Kralevski
authors.forename: S
authors.initials: S
authors.lastname: Rasi
authors.forename: T
authors.initials: T
authors.lastname: Osianlis
mesh_terms: D000328:Adult; D001706:Biopsy / Q000379:methods*; D001757:Blastomeres / Q000166:cytology*; D002869:Chromosome Aberrations; D004624:Embryo Transfer / Q000379:methods; D047108:Embryonic Development; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D011247:Pregnancy; D018873:Pregnancy Rate; D019836:Preimplantation Diagnosis / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity