Received December 09, 2008
Accepted December 23, 2008

Purpose: The goal in the present study was to investigate the effect of quality and origin of sperm on embryo development after intracytoplasmic sperm injection (ICSI), taking into account the early cleavage evaluation. Methods: It was evaluated 175 patients undergoing 193 ICSI cycles. Cycles/patients were divided according to the origin of sperm in: (i) fresh normal semen, (ii) fresh semen with oligospermia, (iii) fresh semen with asthenospermia, (iv) epididymal sperm from obstructive azoospermia and (v) testicular sperm from non-obstructive azoospermia. We evaluated oocyte fertilization, early-cleaved embryo, pregnancy and miscarriage rates. Results: The pregnancy rate was significantly higher when at least one early cleavaged embryo was transfer, (36% versus 23%; with or without early-cleaved embryos transferred, respectively, P = 0.05). No difference was detected in the number of early-cleaved embryos among the groups evaluated. Normal fertilization rate was higher using sperm from the ejaculate compared to epididymal or testicular sperm. Miscarriage rate was higher in the testicular sperm group compared to asthenospermic group. Conclusions: The incidence of early-cleaved embryos has not been influenced by origin of spermatozoa. The quality and origin of sperm seems to influence the fertilization rates, since non ejaculated spermatozoa provided lower normal fertilization rates as well as higher fertilization failure; however, once formed, embryos with satisfactory morphology result in satisfactory pregnancy rates.