The clinical outcomes of ICSI in patients with previous fertilization failure or low fertilization rate after conventional IVF

Objective: To analyze the clinical outcomes of ICSI in patients with previous fertiliza-tion failure or low fertilization rate after conventional IVF. Methods: From Oct. 2001 to May. 2007, 38 ICSI cases with previous total fertilization failure after conventional IVF were allocated to group A. 17 ICSI cases with previous low fertilization rate after conventional IVF were allocated to group B. And 281 ICSI cycles for male factor infertility in the same period were allocated to group C as control group. The fertilization rate,high quality embryo rate,implantation rate and clinical pregnancy rate of three groups were retrospectively analyzed. Results: There were no significant differences in fertilization rate,high quality embryo rate and clinical pregnancy rate among three groups,but implantation rate of group A (14.3%) was significantly lower than that of group B and (C29.5% and 26.0%). Conclusion: For patients who have previous low fertilization rate after conventional IVF,ICSI is a good choice to improve clinical outcomes. But for patients who have previous total fertilization failure after conventional IVF, the implantation rate of ICSI embryos is lower than that of the others. It suggests fertilization failure be due at least partly to occyte abnormity,which results in the descent of embryo development potential.