By affecting the process of spermatogenesis, several genetic, environmental, physiological and nutritional factors can reduce sperm quality and quantity and cause male infertility. The present study aimed to summarize studies conducted on the epidemiological and pathophysiological causes of male infertility, the effects of oxidative stress on poor sperm function and the role of antioxidants in the treatment of male infertility. In the present meta-analysis, the following key words were searched on PubMed, Google scholar, Scopus and Web of Science (1993-2013): male reproductive, male infertility, treatment for male infertility, antioxidant, role of antioxidant therapy, oxidative stress, antioxidant treatment in male fertility, oxidative stress and male infertility and effects of oral antioxidants on sperm quality. Oxidative stress is created by Reactive Oxygen Species (ROS) or free radicals. Although small amounts of ROS are required for sperm functioning, high levels of ROS can affect semen quality which is responsible for %25 of male infertility cases. However, there are antioxidants that have control over the production of ROS and the process of lipid peroxidation by collecting ROS and balancing useful oxidants creating oxidative stress. Thus, using these antioxidants has been recommended for the treatment of male infertility. the administration of L-Carnitine, Selenium, Vitamin E, Vitamin C, Glutathione and coenzyme Q10, as antioxidants, has been proven effective for improving sperm parameters.
