title: Prospective evaluation of blastocyst stage transfer vs. zygote intrafallopian tube transfer in patients with repeated implantation failure.
abstract: OBJECTIVE
  To compare extended culture with blastocyst stage transfer and zygote intrafallopian transfer (ZIFT) in the management of IVF patients with repeated implantation failure.
  
  
  METHODS
  Prospective, nonrandomized study.
  
  
  METHODS
  An IVF unit at a university hospital.
  
  
  METHODS
  Sixty-four infertile patients with more than three previous failed IVF-ET attempts.
  
  
  METHODS
  Patients were allocated to undergo either blastocyst stage transfer (Group 1; n = 32) or ZIFT (Group 2; n = 32).
  
  
  METHODS
  Implantation, clinical pregnancy, and live birth rates.
  
  
  RESULTS
  Patient characteristics and response to stimulation were comparable for both groups. Totals of 84.3% and 97% of the patients underwent blastocyst transfer and ZIFT, respectively. Significantly more embryos were transferred through ZIFT (5.5+/-0.8) as compared with blastocyst transfer (2.3+/-1.4), and there were significantly more cycles with embryo cryopreservation in the ZIFT group as compared to the blastocyst transfer group (15/32 vs. 4/32, respectively). Implantation rate (13.6% vs. 1.4%), clinical pregnancy rate (40.6% vs. 3.1%), and live birth rates (38.7% vs. 0%) were all significantly higher in the ZIFT group as compared to the blastocyst transfer group, respectively.
  
  
  CONCLUSIONS
  Zygote intrafallopian transfer is a powerful clinical tool in the management of patients with RIF. In contrast, blastocyst stage transfer fails to improve the outcome in this poor-prognosis group. The pathophysiology of RIF should be the subject of intense investigation to allow the introduction of appropriate therapeutic measures earlier in the course of treatment.
authors: In Vitro Fertilization Unit, Department of Obstetrics and Gynecology, Edith Wolfson Medical Center, Holon, and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors: David
authors: D
authors: Levran
authors: Jacob
authors: J
authors: Farhi
authors: Hana
authors: H
authors: Nahum
authors: Moshe
authors: M
authors: Royburt
authors: Marek
authors: M
authors: Glezerman
authors: Ariel
authors: A
authors: Weissman
mesh_terms: D000328:Adult; D001723:Birth Rate; D015925:Cryopreservation / Q000706:statistics & numerical data; D010064:Embryo Implantation; D004624:Embryo Transfer; D004622:Embryo, Mammalian; D005260:Female; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D019233:Retreatment; D017211:Treatment Failure; D017388:Zygote Intrafallopian Transfer