By David Douglas
NEW YORK (Reuters Health) Jul 10 - Spinal cord injury before the age of nine can irreversibly interfere with spermatogenesis, a new report suggests.
"The number of patients in this study is very small because there is a relatively low occurrence of spinal cord injury in children, therefore, the data must be interpreted with care," lead author Dr. F. Andrew Celigoj told Reuters Health by email.
However, he said, it appears that "if a child has a spinal cord injury before he reaches puberty, the spinal cord injury may interfere with normal sperm production when that child reaches adulthood. If the spinal cord injury occurs after the child has gone through puberty, then sperm production seems to be similar to that of someone injured in adulthood."
Dr. Celigoj and colleagues at Florida's University of Miami Miller School of Medicine studied 533 men with spinal cord injury and published their findings online June 15th in The Journal of Urology.
All of the men were enrolled in a male fertility research program. In a chart review, the team identified seven men who had been injured between the ages of four and 12. Their current ages ranged from 24 to 38 years and all were able to achieve erections.
Three, who were injured before the age of nine, were azoospermic. One who was injured at the age of 10 years and another injured at the age of 11.6 years had subnormal total sperm counts. The remaining two, who were each injured at the age of 11.9 years, had mean antegrade sperm concentrations within normal ranges.
Overall, 43% of prepubertal subjects were azoospermic, compared to 6.4% of those injured after the age of 12 (p=0.009).
"Although prior work has not been done in this area, these data suggest that there is neurological input at an early age required for spermatogenesis," the authors write.
They add, "Further confirmatory studies are required to understand the age and severity of injury at which semen quality is irreversibly damaged."
They acknowledge that other groups have reported that spinal cord injuries before age nine don't necessarily interfere with spermatogenesis.
"Until more definitive studies can be performed, we recommend that all adult men who sustained a spinal cord injury in childhood, and who wish to father children, undergo an evaluation by a practitioner who is trained in the specialized procedures required to manage infertility in men with spinal cord injury," Dr. Celigoj said.
J Urol 2012.