The relative distribution of viable sperm in the antegrade and retrograde portions of ejaculates obtained after electrostimulation*†*Supported by the Regional Spinal Cord Injury Center of the Delaware Valley and the National Institute for Disability Research and Rehabilitation, grant no. G008535135, Washington, D.C.†Presented at the 15th Annual Meeting of the American Society of Andrology, Columbia, South Carolina, April 6 to 9, 1990.