[Intracytoplasmic sperm injection can improve the fertilization limitation following in vitro fertilization during previous cycles].

OBJECTIVE: To evaluate whether or not intracytoplasmic sperm injection (ICSI) can improve previous fertilization limitation on conventional in vitro fertilization (IVF). METHODS: One hundred and thirty-six completed cycles in 113 patients with ICSI treatment were grouped. Group 1 was 106 cycles perform ICSI because of male factor, and group 2 was other 30 cycles with the history of fertilization failure and fertilization rate < 20% on conventional IVF, also assembling the cycles in group 2 according to the fertilization rate. RESULTS: There was no significant difference between two groups in the rates of normal fertilization(70.49% vs 72.02%), good quality embryos (38.28% vs 38.81%), and clinical pregnancy (40.57% vs 40.00%) (P > 0.05). The fertilization rate of a majority of cycles (70.00%, 21/30) in group 2 was higher than 50%, and the mean of fertilization rates was 79.79%. CONCLUSION: ICSI can improve the fertilization limitation following IVF during previous cycles, and the fertilization rates was similar to those treated ICSI because of male factor.