Thirty-six men (aged 18-42 years, average age 27 years) with known spinal cord lesions for 0.3-39 years and levels of the lesions from C3 incomplete to L1 complete were submitted to penile vibrations with the objective to obtain reflex ejaculation. Sperm cells were demonstrated in a total of 27 of the participants, antegrade ejaculation in 16 cases and 11 retrograde ejaculations. In general, the semen quality was very poor with reduced total number of spermatozoa and increased percentage of immobile and/or morphologically abnormal spermatozoa compared with normal values. In connection with the vibration procedures, three cases of autonomous hyperreflexia followed by transient slight headache which did not require treatment occurred while an isolated case was treated with 0.5 mg glycerine nitrate (Nitromex) administered sublingually with good effect. No other side effects were observed.