Objective: To compare extended culture with blastocyst stage transfer and zygote intrafallopian transfer (ZIFT) in the management of IVF patients with repeated implantation failure.
Design: Prospective, nonrandomized study.
Setting: An IVF unit at a university hospital.
Patient(s): Sixty-four infertile patients with more than three previous failed IVF-ET attempts.
Intervention(s): Patients were allocated to undergo either blastocyst stage transfer (Group 1; n = 32) or ZIFT (Group 2; n = 32).
Main outcome measure(s): Implantation, clinical pregnancy, and live birth rates.
Result(s): 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.
Conclusion(s): 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.