SUCCESS RATES FOLLOWING INTRACYTOPLASMIC SPERM INJECTION ARE IMPROVEDBY USING ZIFT VS IVF FOR EMBRYO-TRANSFER

Purpose: The purpose of this study was to analyze whether the mode of embryo transfer (ZIFT vs IVF) affected the outcome in intracytoplasmic sperm injection (ICSI) cycles. Methods and Results: Eighty-two ICSI c ycles (42 ZIFT and 40 IVF) were analyzed. Several variables, including patient age and weight numbers of mature eggs collected injected, and fertilized, fertilization rare, number of fertilized eggs obtained pe r cycle, numbers of zygotes/embryos transferred clinical pregnancy rar e, and implantation rate, were compared. Mean patient age and weight w ere identical. The mean number of mature eggs collected and injected a nd fertilization rate were significantly higher in the ZIFT group, how ever the mean numbers of zygotes/embryos transferred were identical. T he clinical pregnancy and implantation rates in ZIFT cycles (52.3 and 23.2% respectively) were significantly higher than in IVF cycles (17.5 and 9.7%). Conclusions: These data suggest that ZIFT is the more appr opriate method for transfer of ICSI-derived embryos.