New Developments for the Enhancement of Male Reproductive Health Using Antioxidant Therapy: A Critical Review of the Literature

Abstract

Oxidative stress is a well-established cause of male infertility. Reactive oxygen species (ROS), produced by sperm and activated leukocytes within the male reproductive tract, are present at higher concentrations in infertile men’s semen and have been conclusively shown to impair sperm function leading to infertility and possible long-term health consequences for any child conceived. In this chapter, we critically analyse the published studies that have attempted to treat male infertility by the reduction of leukocyte production of ROS (anti-inflammatory action), the direct neutralization of ROS by antioxidants or the fortification of sperm against ROS attack. Overall, there is reasonably good evidence that some antioxidant and anti-inflammatory therapies can significantly reduce oxidative damage to sperm DNA and improve sperm membrane function (motility and sperm fertilization capacity). However, what is still contentious is whether these improvements in sperm quality translate into an increase in natural conception rates for infertile couples. While several relatively small studies have shown some antioxidant therapies to assist both in vivo and in vitro conception, larger more definitive studies will be required before antioxidant therapy becomes an established medical practice for infertile males.