Does Antioxidant Administration Improve Sperm Quality in Infertile Men

Infertility affects up to 15% of couples trying to conceive with the male factor contributing in about 50% of cases. Oxidative stress (OS) has been found as one of the many factors causing male infertility, by inducing sperm damage. OS causes cell damage due to the raised production of reactive oxygen species (ROS), that overcome the antioxidant mechanisms of the human body. ROS are oxidizing agents that are produced as a by-product of oxygen metabolism, having at least one free electron. Due to this free electrone in their outer layer, the form very active or unstable substances. While small amounts of ROS are necessary for the proper function of sperm, increased amounts have a negative effect on sperm quality and can harm its fertility potential, thus inducing male infertility.

Spermatozoa were the first cells found to be sensitive to OS, as they lack the necessary repair cytoplasmic enzyme systems, thus being unable to repair damage. In addition, their cytoplasmic membranes are rich in polyunsaturated fatty acids (PUFAs), making them highly susceptible to oxygen-induced damage, such as lipid peroxidation (LPO). Rapid loss of intracellular adenosine triphosphate (ATP) by LPO, is responsible for axial damage, morphological damage to the sperm neck and reduced sperm motility; these events contribute to reduced sperm motility.

OS has also been associated with reduced fertilization, delayed intrauterine growth, miscarriages, birth defects (including autism) and childhood cancer. ROS found in semen come from a variety of endogenous and exogenous factors. Human sperm includes mature and immature sperm cells, leukocytes, and white blood cells. The leukocytes (mainly neutrophils and macrophages) and the immature spermatozoa are considered the major endogenous sources of ROS, whereas lifestyle, such as smoking, excessive alcohol consumption and other environmental factors such as radiation and toxins may contribute to the production of exogenous ROS.

As oxidative stress (OS) results from the imbalance of ROS overproduction and the reduced capacity of sperm antioxidant systems, many studies have aimed to improve sperm quality by administering antioxidant therapeutic regimens. In general, antioxidant therapy involves the administration of oral antioxidants, and the in vitro addition of antioxidants to culture media that are used for sample preparation in assisted reproduction techniques (ART). Many different antioxidants combinations have been studied. More and more studies have shown the beneficial effect of antioxidants on reducing sperm fragmentation and improving sperm quality. Agarwal & Sekhon's study showed a positive correlation between antioxidant therapy and various semen parameters. However, no firm conclusion regarding the beneficial effect of oral antioxidants can be made, as the majority of available studies had small sample size, used different antioxidant combinations, and the techniques that were used for the detection of ROS and DNA fragmentation index (DFI) were not standardized.

AIM OF THE STUDY The purpose of this randomized clinical trial is to assess the effect of oral antioxidant administration to infertile men, by evaluating semen variables, sperm DFI and levels of ROS.Oral antioxidants or placebo will be given for 3 consecutive months.