Objectives: The role of zinc therapy on infertility caused by defective sperm quality is examined.
Study design: In this study, 100 men with asthenozoospermia were randomised into two groups--250 mg twice daily zinc therapy for 3 months and no therapy. The patients were followed up for another 6 months. Sperm parameters, circulating antisperm antibodies, sex hormones and T helper cytokines were evaluated before and after treatment for the two groups.
Results: There was significant improvement in the sperm quality; sperm count (P<.02), progressive motility (P<.05), fertilising capacity (P<.01) and a reduction in the incidence of antisperm antibodies (P<.01). Zinc/cadmium was higher in the zinc therapy group (P<.02). T helper cytokine, interleukin-4 level was significantly higher after zinc therapy (P<.02) while TNFalpha showed a significant decrease (P<.05).
Conclusions: Zinc therapy has a role in improving sperm parameters in men with asthenozoospermia, probably through its membrane stabilising effect as an antioxidant and its effect on cellular and humoral immunity by reducing the levels of antisperm antibodies and TNFalpha and increasing that of IL-4.