title: Early compaction on day 3 may be associated with increased implantation potential.
abstract: OBJECTIVE
  To determine whether day 3 embryos exhibiting early compaction have an improved implantation potential compared to embryos without compaction.
  
  
  METHODS
  A retrospective cohort study.
  
  
  METHODS
  Hospital-based academic medical center.
  
  
  METHODS
  Women <38 years of age undergoing IVF cycles between November 2001 and December 2004 having a day 3 transfer of one or two embryos with >8 cells.
  
  
  METHODS
  Standard IVF protocol.
  
  
  METHODS
  Compaction grading and implantation rates of 1,047 embryos as related to fragmentation of >or= 8-cell embryos in patients with either 0% or 100% implantation.
  
  
  RESULTS
  Compaction grading was strongly associated with implantation potential; however, the direction of this effect depended on the degree of fragmentation. In embryos with <10% fragmentation, implantation rates increased with the degree of compaction (grade 1, 25%; grade 2, 33%; and grade 3, 47%); in embryos with >or=10% fragmentation, the effect was reversed (grade 1, 38%; grade 2, 20%; and grade 3, 9%).
  
  
  CONCLUSIONS
  Assessing the degree of compaction can be a valuable addition to traditional morphologic assessment in identifying optimal embryos for transfer on day 3.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Christine C
authors.initials: CC
authors.lastname: Skiadas
authors.forename: Katharine V
authors.initials: KV
authors.lastname: Jackson
authors.forename: Catherine
authors.initials: C
authors.lastname: Racowsky
mesh_terms: D000328:Adult; D018929:Cell Culture Techniques / Q000379:methods*; D002478:Cells, Cultured; D015331:Cohort Studies; D010064:Embryo Implantation / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008597:Menstrual Cycle / Q000502:physiology*; D009865:Oocytes / Q000166:cytology* / Q000502:physiology*; D011247:Pregnancy; D012189:Retrospective Studies