PURPOSE Based on the findings of a previous study of pressure differentials in the external and internal urinary sphincters during electroejaculation we determined whether semen retrieval in men with spinal cord injury would be improved by interrupting current delivery during electroejaculation. MATERIALS AND METHODS We tested continuous versus interrupted current delivery in the same group of 12 men with spinal cord injury. Patients underwent a mean of 4 randomly assigned continuous or interrupted trials 4 to 8 weeks apart. Antegrade and retrograde semen parameters were analyzed per trial. Multiple trials of each method per patient were averaged and semen parameters by the continuous and interrupted methods were compared. RESULTS Interrupted delivery resulted in significantly greater mean antegrade volume versus continuous delivery (2 versus 0.9 cc). In this antegrade fraction mean total sperm count and mean total motile sperm was higher for interrupted (130 million and 35 million) versus continuous (79 million and 26 million, respectively) delivery. The mean retrograde total sperm count was 4-fold higher for continuous (120 million) versus interrupted (29 million) delivery. In the total ejaculate of the combined antegrade and retrograde fractions the mean total sperm count and mean total motile sperm were not significantly different for the 2 methods. CONCLUSIONS Each method resulted in a similar mean total sperm count and total motile sperm in the total ejaculate but a higher proportion of sperm was found in the antegrade fraction using the interrupted method. We recommend interrupted current delivery as the technique of choice when electroejaculation is performed to obtain sperm for fertilization.