Comparing intracytoplasmic sperm injection and in vitro fertilization in patients with single oocyte retrieval

Objective: To compare the efficacy of intracytoplasmic sperm injection (ICSI) and conventional IVF in patients with favourable and poor sperm parameters in which only a single oocyte was available for insemination. Design: Retrospective analysis. Setting: University-affiliated IVF center. Patient(s): A total of 311 patents (425 cycles) who underwent either stimulated or spontaneous IVF cycles that resulted in single oocyte retrieval. Intervention(s): the ICSI was indicated when fertilization failure was anticipated because of sperm quality or other confounding female factors. Main Outcome Measure(s): Fertilization rates and pregnancy rates (PRs) were analyzed according to the women's age (<= 39 or > 39 years), sperm quality, and mode of insemination. Result(s): In patients < 39 years old with favourable semen quality, ICSI and standard insemination produced similar fertilization rates (67.1% vs. 75.0%) and ORs (0.0 vs. 8.2%). Conversely, in cases with apparent lower semen quality, ICSI gave a significantly higher fertilization rate (82.4% vs. 44.2%) but no significant difference in PRs (14.6% vs. 4.7%). In patients > 39 years old and with favorable semen quality, ICSI and standard insemination produced similar fertilization rates (82.4% vs. 68.4%) and PRs (0.0 vs. 1.1%). The ICSI for lower semen quality, however, produced both higher fertilization rates (84.0% vs. 52%) and higher PRs (8.0% vs 0). Conclusion(s): Our results suggest that in poorly responding patients, semen quality should remain the most important determinant when considering whether to perform ICSI. We have found that the values of 20 x 10(6)/mL and 35% motility are good predictors of success in such patients.