Intrauterine insemination with semen of oligozoospermic men: effectiveness of the continuous-step density gradient centrifugation technique.

There has been an argument as to whether the intrauterine insemination (IUI) substantially improves pregnancy rate in cases of oligoasthenozoospermia. The present study evaluates the efficiency of the IUI with the use of the life table analysis. The insemination was performed after washing and concentrating sperm using the continuous-step density gradient centrifugation reported in our previous papers. The number of IUI cycles studied was 222 (46 couples), in 13 cases of which pregnancy was established with a pregnancy rate of 28.3%. The cumulative probability of conception reached to 57% at the eleventh cycles of the IUI treatment. These results suggest that the potential efficiency of the IUI for the oligo-asthenozoospermic cases is high if the sperm is processed in a proper method.