[Clinical outcomes of intracytoplasmic sperm injection (ICSI) and ISCI following fertilization failure in conventional IVF: a comparative analysis].

OBJECTIVE: To evaluate the clinical outcomes of intracytoplasmic sperm injection (ICSI) in patients with previous fertilization failure in conventional in vitro fertilization (IVF) procedures. METHODS: Between January 2007 and December 2007, 27 ICSI cycles following a previous fertilization failure in conventional IVF (group A) and 57 direct ICSI cycles using ejaculated spermatozoa (group B) were performed, and the clinical outcomes of the two groups were analyzed. RESULTS: The fertilization rate per cycle of ICSI following a fertilization failure in conventional IVF was significantly higher than that of conventional IVF [(80.4-/+16.6)% vs (32.3-/+30.3)%, P<0.01]. The normal fertilization rate, high-quality embryo rate, clinical pregnancy rate per cycle in group A showed no significant differences from those in group B [(77.14-/+15.98)% vs (70.59-/+21.53)%, (28.68-/+23.86)% vs (27.18-/+23.97)%, and 48.1% vs 54.4%, respectively, P>0.05]. The cleavage rate and transferable embryos per cycle in group A were significantly higher than those in group B [(96.66-/+6.55)% vs (92.33-/+19.41)%, 2.67-/+0.56 vs 2.12-/+0.57, respectively, P<0.05]. CONCLUSION: ICSI after a previous fertilization failure of conventional IVF may significantly improve the fertilization rate and clinical outcomes of a second IVF-ET cycle.