Comparison of the fertilizing capability of spermatozoa from ejaculates, epididymal aspirates and testicular biopsies using intracytoplasmic sperm injection

A prospective study was carried out to compare the fertilizing capabilityand pregnancy outcome following intracytoplasmic sperm injection (ICSI)using spermatozoa obtained from ejaculates, or surgically from epididymisor seminiferous tubules. A total of 77 ICSI cycles (one per patient) wasincluded. In all, 28 patients had severe oligoasthenoteratozoospermia, 19patients had obstructive azoospermia and 30 patients had non-obstructiveazoospermia. The main outcome measures were fertilization rate per injectedmetaphase II oocyte and the clinical pregnancy rate per embryo transferredback to the female recipients. In patients with severeoligoasthenoteratozoospermia, the fertilization and pregnancy rates were 79and 25 %. In patients with obstructive azoospermia, for whom epididymalspermatozoa were used, these were 75 and 28%, and in the non-obstructivegroup for which testicular spermatozoa were used for injection, they were69 and 21% respectively. These rates were not significantly different inthe three groups (P = 0.85 and P = 0.14 respectively), suggesting thatspermatozoa from the ejaculates and epididymal or testicular biopsies areable to fertilize equally by using ICSI. Live birth per embryo transfer wassignificantly reduced in patients with non-obstructive azoospermia comparedto the other two groups. The high abortion rate (50%) in the group in whichtesticular spermatozoa were used raises doubts about the developmentalcompetence of such embryos.