Invited review
Significance of oxidative stress in human reproduction

The aim of this review is to summarize the role of free radicals and oxidative stress in the pathophysiology of human reproduction. As our knowledge of human reproduction and factors contributing to infertility continues to expand at a phenomenal rate, it is evident that oxidative stress (OS) has been implicated in both male and female infertility. Reactive oxygen species function via proinflammatory cytokines and this mechanism has been proposed as a common underlying factor for endometriosis, hydrosalpinx and various other pathologies affecting the female reproductive process. This review highlights the role of OS in the above mentioned female pathologies as well as pre-eclampsia, hydatidiform mole, unexplained infertility, premature ovarian aging and recurrent pregnancy loss. Oxidative stress, sperm DNA damage and apoptosis have been implicated in male infertility, as seen in male pathologies highlighted in this review – varicocele, cryptorchidism and infection. Substantial evidence provides a positive correlation between elevated reactive oxygen species and poor fertility outcome. The literature provides evidence suggesting treatment with antioxidant supplementation provides an effective therapeutic modality for OS in human reproduction, however further studies are warranted to provide answers on their safety and effectiveness.