Despite the increased use of ICSI, there is no clear evidence that ICIS is more effective than conventional IVF for non-male factor infertility. There are currently few randomized controlled studies that compared the two modalities in the case of non-male factor infertility. In a randomized controlled trial that included 415 couples with non-male factor infertility and women younger than 37 years of age, conventional IVF was associated with better fertilization and implantation rates than ICSI but with comparable live birth rates. In addition, studies have not shown an advantage for ICSI over conventional IVF in the case of unexplained infertility, low oocyte yield or routine use to decrease the incidence of fertilization failure.