title: Comprehensive chromosome screening of polar bodies and blastocysts from couples experiencing repeated implantation failure.
abstract: OBJECTIVE
  To identify and transfer cytogenetically normal embryos after screening all chromosomes of first and second polar bodies (PBs) or trophectoderm samples with the use of comparative genomic hybridization.
  
  
  METHODS
  Clinical research study.
  
  
  METHODS
  In vitro fertilization clinic referring samples to a specialist preimplantation genetic diagnosis laboratory.
  
  
  METHODS
  Thirty-two couples with repeated implantation failure.
  
  
  METHODS
  Zygotes from patients with repeated implantation failure and poor response to ovarian stimulation underwent PB biopsy. Patients with repeated implantation failure who were candidates for blastocyst transfer received trophectoderm biopsy. Zygotes or blastocysts were vitrified while chromosome analysis took place. Euploid embryos were transferred during a subsequent cycle.
  
  
  METHODS
  Cytogenetic status and implantation and pregnancy rates.
  
  
  RESULTS
  The oocyte and blastocyst aneuploidy rates were 65.5% and 45.2%, respectively. Abnormalities affecting all chromosomes were detected. Implantation and pregnancy rates for the patients with PB biopsy were 11.5% and 21.4%, respectively, whereas for patients receiving blastocyst analysis they were 58.3% and 69.2%.
  
  
  CONCLUSIONS
  Initial results for patients of advanced maternal age (39.8 years) with repeated implantation failure and poor ovarian response were encouraging. However, further study is required to confirm whether or not screening is beneficial. Blastocyst analysis was associated with high pregnancy rates, suggesting that comprehensive chromosome screening may assist patients with repeated implantation failure capable of producing blastocysts in achieving pregnancies.
authors.affiliation: Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Oxford, United Kingdom. elpida.fragouli@obs-gyn.ox.ac.uk
authors.forename: Elpida
authors.initials: E
authors.lastname: Fragouli
authors.forename: Mandy
authors.initials: M
authors.lastname: Katz-Jaffe
authors.forename: Samer
authors.initials: S
authors.lastname: Alfarawati
authors.forename: John
authors.initials: J
authors.lastname: Stevens
authors.forename: Pere
authors.initials: P
authors.lastname: Colls
authors.forename: N-neka
authors.initials: NN
authors.lastname: Goodall
authors.forename: Sophia
authors.initials: S
authors.lastname: Tormasi
authors.forename: Cristina
authors.initials: C
authors.lastname: Gutierrez-Mateo
authors.forename: Renata
authors.initials: R
authors.lastname: Prates
authors.forename: William B
authors.initials: WB
authors.lastname: Schoolcraft
authors.forename: Santiago
authors.initials: S
authors.lastname: Munne
authors.forename: Dagan
authors.initials: D
authors.lastname: Wells
mesh_terms: D000026:Abortion, Habitual / Q000175:diagnosis / Q000235:genetics*; D000328:Adult; D001755:Blastocyst / Q000166:cytology* / Q000378:metabolism; D002478:Cells, Cultured; D002877:Chromosomes, Human / Q000235:genetics / Q000378:metabolism; D055028:Comparative Genomic Hybridization; D020732:Cytogenetic Analysis; D046149:Embryo Culture Techniques; D010064:Embryo Implantation / Q000235:genetics; D020964:Embryo Loss / Q000175:diagnosis / Q000235:genetics*; D005191:Family Characteristics; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D019836:Preimplantation Diagnosis / Q000379:methods