Infertility in men with spinal cord injury.

Infertility is a significant and frustrating problem for many men after spinal cord injury. The two major causes are poor semen quality and ejaculatory dysfunction. Factors attributed to poor semen quality include stasis of prostatic fluid, testicular hyperthermia, recurrent urinary tract infections, abnormal testicular histology, possible changes in the hypothalamic-pituitary-testicular axis, possible sperm antibodies, chronic long-term use of various medications, and type of bladder management. Further work is needed to define the impact and importance of each of these factors. Ejaculations are reported to occur in only 5% of men with spinal cord injury (SCI) who have complete upper motor lesions and 18% of those who have complete lower motor lesions. Ejaculations occur in up to 70% of men with incomplete lesions. Methods that have been used to induce an ejaculate include intrathecal neostigmine, subcutaneous physostigmine, direct aspiration of sperm from the vas deferens, vibratory stimulation, electroejaculation, and direct stimulation of the hypogastric nerve. The most commonly used methods in the United States are electroejaculation and vibratory stimulation; using these two methods, ejaculates can be obtained up to 85% and 59% of the time, respectively. Each of these methods has advantages and disadvantages. Particular care needs to be given to monitoring men undergoing these procedures who are prone to autonomic dysreflexia. The future outlook is encouraging once improved technology for obtaining semen and various methods to assist reproduction, such as in vitro fertilization, are available.