Use and Outcomes of Intracytoplasmic Sperm Injection for Non-Male Factor Infertility

Abstract

Although the use of intracytoplasmic sperm injection (ICSI) continues to increase in the United States, its effectiveness for patients without male factor infertility has never been convincingly demonstrated. In these patients, success rates are generally lower in those who use ICSI. This technique was evaluated in 486 patients without a diagnosis of male factor infertility who had 696 consecutive assisted reproductive technology (ART) cycles, 597 with IVF and 99 with ICSI. The 2 groups were similar except for higher rates of unexplained infertility and a previous ART cycle in the ICSI group and a higher rate of previous fertility in the IVF group. More oocytes were harvested in the IVF than in the ICSI group (9.0 versus 8.2), but the difference was not statistically significant. However, significantly more oocytes underwent IVF than ICSI (9.0 versus 7.4). The percentage of oocytes undergoing IVF also was significantly greater than the percentage undergoing ICSI. The difference in the mean numbers of oocytes fertilized, 6.6 for IVF and 5.1 for ICSI, was statistically significant. The fertilization rate was higher in the IVF group (74.1% versus 69.1%), but this difference was not significant. Rates of complete failure of fertilization were 3.2% for IVF and 4.0% for ICSI. In each group, 2.7 embryos on average were replaced. Approximately 95% of patients in each treatment group had at least 1 embryo replaced. There was no group difference in live birth rates. Logistic regression analysis revealed that a previous ART cycle was associated with ICSI, but choice of treatment could not be related to rates of fertilization, pregnancy, or live birth. This study failed to provide clear evidence of improved outcomes with ICSI compared with IVF in cases of nonmale factor infertility. The investigators find it difficult to justify this more expensive—and possibly less safe—procedure without clear evidence that it is beneficial.