Impact of fertilization history and semen parameters on ICSI outcome

The objectives of this study were (1) to investigate intracytoplasmic sperm injection (ICSI) outcome according to its indications, i.e., a history of failed or poor fertilization and unsuitable sperm parameters for conventional IVF, and (2) to examine the impact of a female's age, sperm concentration, motility, morphology, presence of antisperm antibodies, and hemizona assay (HZA) results on overall outcome.

Two hundred seventy-nine ICSI cycles performed in 207 couples were retrospectively evaluated.

Clinical pregnancy and delivery rates were 36.8 and 29.8% for patients with prior failed fertilization, 23.2 and 17.8% for patients who had prior poor fertilization, and 28.6 and 21.3% for patients with unsuitable sperm parameters. The differences among all groups were found to be insignificant. There was a significant, negative correlation between a female's age and pregnancy results. No difference was found in the three basic sperm parameters between those patients who produced and those who did not produce a pregnancy, but the fertilization rate was significantly higher in patients with more adequate sperm parameters. Although there was a trend toward a better fertilization rate in patients with a hemizona index (HZI) greater than 30 (indicative of a superior sperm-zona pellucida binding capacity) than in those with a HZI less than 30, the difference was not significant. There were no differences in fertilization rate according to the presence or absence of antisperm antibodies.

Fertilization history in a conventional IVF cycle has no effect on success rates following ICSI, and there is no correlation among the basic sperm parameters, the presence of antisperm antibodies, and pregnancy rates.