Objective : To evaluate the cumulative pregnancy rate(CPR) of in vitro fertilization and embryo transfer(IVF-ET) with intracytoplasmic sperm injection(ICSI). Methods : Medical records of 260 infertile patients undergoing 519 cycles of IVF-ET with ICSI from January, 1994 to December, 1999 were retrospectively reviewed. The CPR beyond 12 weeks of gestation was estimated by Kaplan-Meier method. The CPRs were compared by log-rank test between groups divided by age of patients, indication of ICSI, and method of sperm retrieval for ICSI. Results : As 70 patients achieved an on-going pregnancy after IVF-ET with ICSI, the PR was 26.9% per patient and 13.5% per cycle. The overall CPR was 54.9% after 6 cycles of IVF-ET with ICSI. As expected, age had a significant strong effect on the CPR; CPRs afer 4 cycles of ICSI were 61.8% in the age group of 30 years(n=81), 43.7% in 31-35 years(n=106), and 15.3% in 36 years(n=73). There was no significant difference in the CPR between abnormal semen analysis group(n=184) and prior low fertilization rate group(n=66). In abnormal semen analysis group, the CPR of surgically retrieved sperm subgroup(n=60) was not significantly different from that of ejaculated sperm subgroup(n=124). Conclusions : The CPR of IVF-ET with ICSI was presented, and it could be of much help in the clinical counseling of IVF-ET patients. ICSI technique could be used successfully for IVF-ET in infertile couples who had the male factor infertility or the past history of low fertilization rate in the previous cycles.