Association of elevated estradiol with remote testicular trauma in young infertile men.

OBJECTIVE: To determine the incidence of remote testicular trauma and of possible related permanent hormonal and seminal changes in infertile men. DESIGN: Retrospective clinical study of hormonal and seminal parameters in a subpopulation of infertile men. SETTING: Andrology Clinic in an academic research environment. PARTICIPANTS: Infertile men, with and without history of remote testicular trauma, and fertile volunteers. MAIN OUTCOME MEASURES: Percentage of infertile men with history of blunt testicular trauma, concentrations of reproductive hormones, and semen parameters. RESULTS: Significant remote blunt testicular trauma was reported by 16.8% of infertile men. This had occurred 2 to 17 years (mean, 16.4 years) before evaluation, mostly with contact sports at adolescent age. Estradiol concentrations after testicular trauma were 19% and 25% higher than in infertile men without history of testicular injury and in fertile controls. Elevated E2 levels did not correlate with T. Infertile men with and without history of testicular trauma showed changes in seminal parameters. CONCLUSION: The incidence of remote blunt testicular trauma in infertile men is unexpectedly high. After injury, FSH-stimulated aromatization of T may increase testicular E2 production, interfere with spermatogenesis, and cause infertility. Consistent use of protective devices in contact sports is recommended.