Effect of Lycopene Supplementation on Infertility in Men: A Systematic Review on Clinical Trial Studies

Background and Objectives: Infertility is a reproductive disorder that a person has no reproductive ability, despite having a regular and unprotected sex for at least one year. Studies have shown that antioxidants can play an important role in improving infertility. The aim of this study was to summarize the data from clinical trial articles on the effects of lycopene supplementation on different parameters of sperm in infertile men. Methods: In the present systematic review study on the researches carried out on the relationship between lycopene and infertility, the studies on the effect of lycopene supplementation on male infertility, were investigated through PubMed, Scopus, ISI, and Google Scholar databases between 1990 and 2018 using keywords of lycopene, antioxidant, sperm parameters, male infertility, and semen parameters. Results: In most clinical trials, lycopene has a significant effect on the number, motility, and morphology of sperm, and also significant changes were seen with changes in antioxidant capacity and oxidative factors that have a significant role in changing sperm parameters. Changes in the surface of the receptors as well as oxidative enzymes, such as glutathione peroxidase, superoxide dismutase, and catalase were among other results observed in the studies. However, in some studies, no significant effect was found in sperm parameters. Conclusion: The results of this study indicated that lycopene supplementation can have a positive effect on sperm parameters, antioxidant capacity, and antioxidant enzymes, but due to the low number of studies, especially in the human community, more trials are needed in this field.