Spasticity is a common sequel of spinal cord injury (SCI) with well documented effects on daily activities and increased morbidity. In the course of our fertility studies using rectal probe electrostimulation (RPES) and SCI men to produce ejaculation, we observed that a majority of the men experienced significant improvement in their spasticity for many hours. This paper describes a preliminary effort to quantitate this phenomenon in 14 consecutive subjects treated for anejaculation on 65 occasions in our SCI Fertility Clinic. The effectiveness of RPES on spasticity was evaluated by pre- and post-RPES subject assessment and neurological examinations and follow-up self reports via telephone interviews. Six of the 14 patients (42%) experienced excellent relief following 30 of 33 RPES treatments; 4 (29%) had good to fair relief following 14 of 15 RPES treatments and 4 (29%) had no effect on all 17 RPES trials. The mean duration of relief was 9 hours (3-24). There was no relation between subject age, age of injury, level or completeness of injury or ejaculatory response with relief of spasticity. All men taking medications felt RPES was more effective than drugs in relieving spasms. No untoward effects were reported and 7 (50%) said they would use a home model for daily RPES, if available.