Intracytoplasmic sperm injection and conventional in vitro fertilization for sibling oocytes in cases of unexplained infertility and borderline semen

Purpose: In a prospective study, conventional IVF and intracytoplasmic sperm injection (ICSI) were performed on sibling oocytes of 22 patients with unexplained infertility (Group A) and 24 patients with borderline semen (Group B).Results: In Group A, there was no significant difference (P=0.070) in the fertilization rate per oocyte between ICSI (63%) and conventional IVF (50.7%), however, there was total failure of fertilization in conventional IVF in 5 of the 22 patients with IVF and none in ICSI. In group B, there was a significant difference (P<0.001) between the fertilization rate per oocyte in ICSI (59%) and conventional IVF (27.1%). There was total failure of fertilization in 11 patients after conventional IVF and none after ICSI.Conclusions: The study showed that 22.7% of unexplained infertility and 45.8% of patients with borderline semen would have lost their chance of embryo transfer completely because of total failure of fertilization if ICSI was not performed on some oocytes in this cycle.Presented in part at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, Vienna, Austria, April 3–7, 1995.