title: Optimal euploid embryo transfer strategy, fresh versus frozen, after preimplantation genetic screening with next generation sequencing: a randomized controlled trial.
abstract: OBJECTIVE
  To compare two commonly used protocols (fresh vs. vitrified) used to transfer euploid blastocysts after IVF with preimplantation genetic screening.
  
  
  METHODS
  Randomized controlled trial.
  
  
  METHODS
  Private assisted reproduction center.
  
  
  METHODS
  A total of 179 patients undergoing IVF treatment using preimplantation genetic screening.
  
  
  METHODS
  Patients were randomized at the time of hCG administration to either a freeze-all cycle or a fresh day 6 ET during the stimulated cycle.
  
  
  METHODS
  Implantation rates (sac/embryo transferred), ongoing pregnancy rates (PRs) (beyond 8 weeks), and live birth rate per ET in the primary transfer cycle.
  
  
  RESULTS
  Implantation rate per embryo transferred showed an improvement in the frozen group compared with the fresh group, but not significantly (75% vs. 67%). The ongoing PR (80% vs. 61%) and live birth rates (77% vs. 59%) were significantly higher in the frozen group compared with the fresh group.
  
  
  CONCLUSIONS
  Either treatment protocol investigated in the present study can be a reasonable option for patients. Freezing all embryos allows for inclusion of all blastocysts in the cohort of embryos available for transfer, which also results in a higher proportion of patients reaching ET. These findings suggest a trend toward favoring the freeze-all option as a preferred transfer strategy when using known euploid embryos.
  
  
  BACKGROUND
  NCT02000349.
authors.affiliation: Oregon Reproductive Medicine, Portland, Oregon; School of Biosciences, University of Kent, Canterbury, United Kingdom. Electronic address: alison@portlandivf.net.
authors.forename: Alison
authors.initials: A
authors.lastname: Coates
authors.affiliation: Reprogenetics, Portland, Oregon; School of Biosciences, University of Kent, Canterbury, United Kingdom.
authors.forename: Allen
authors.initials: A
authors.lastname: Kung
authors.affiliation: Oregon Reproductive Medicine, Portland, Oregon.
authors.forename: Emily
authors.initials: E
authors.lastname: Mounts
authors.affiliation: Oregon Reproductive Medicine, Portland, Oregon.
authors.forename: John
authors.initials: J
authors.lastname: Hesla
authors.affiliation: Oregon Reproductive Medicine, Portland, Oregon.
authors.forename: Brandon
authors.initials: B
authors.lastname: Bankowski
authors.affiliation: Oregon Reproductive Medicine, Portland, Oregon.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barbieri
authors.affiliation: Koc University School of Medicine, Istanbul, Turkey.
authors.forename: Baris
authors.initials: B
authors.lastname: Ata
authors.affiliation: Reprogenetics, Livingston, New Jersey.
authors.forename: Jacques
authors.initials: J
authors.lastname: Cohen
authors.affiliation: Reprogenetics, Livingston, New Jersey.
authors.forename: Santiago
authors.initials: S
authors.lastname: Munné
mesh_terms: D000328:Adult; D001706:Biopsy; D001755:Blastocyst / Q000502:physiology*; D015925:Cryopreservation; D046149:Embryo Culture Techniques; D010064:Embryo Implantation; D004624:Embryo Transfer / Q000009:adverse effects; D005260:Female; D005298:Fertility; D005307:Fertilization in Vitro / Q000009:adverse effects; D005820:Genetic Testing; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007246:Infertility / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D050498:Live Birth; D009922:Oregon; D011003:Ploidies; D011237:Predictive Value of Tests; D011247:Pregnancy; D018873:Pregnancy Rate; D019836:Preimplantation Diagnosis / Q000379:methods*; D012307:Risk Factors; D016896:Treatment Outcome; D058989:Vitrification
keywords: PGS; aneuploidy; embryos; transfer