Rectal probe electroejaculation is effective in procuring sperm from spinal cord injured patients with ejaculatory incompetence. The seminal quality in these patients is usually suboptimal and the motility is almost always low. We conducted an in vitro experiment to determine whether the heat and current generated during rectal probe electroejaculation impaired sperm motility or forward progression, or if the poor semen quality is the result of existing testicular dysfunction.