At present, no single laboratory test can accurately predict the fertilizing capacity of spermatozoa. A battery of clinical tests that are significant predictors of fertilization are needed to successfully treat infertile men. Identification of functional predictors of fertilization is important in devising protocols to improve sperm quality. One area of research in our laboratory is to design an algorithm that can assist the clinician in selecting the most appropriate assisted reproductive procedure based on the nature of sperm defects, assuming that the female partner is normal. Sperm dysfunction can be determined by biochemical markers of sperm function such as creatine kinase levels, generation of reactive oxygen species (ROS) and extent of lipid peroxidation. Similarly, sperm-functlon tests, such as acrosome reaction, mannose receptor assay and hamster egg penetration assay, provide information on fertilizing capacity.
We are currently studying the role of ROS in the pathophysiology of varicocele, which is the most common correctable cause of male infertility. Whether varicocele correction in combination with antioxidant supplementation (glutathione, vitamin E) is more beneficial than varicocele correction alone in improving sperm quality and pregnancy rates is the focus of this study. Another area of interest is the improvement of semen quality in cryopreserved semen specimens, minimizing sperm damage due to reactive oxygen species generation and lipid peroxidation. The role of antioxidants in the treatment of male infertility is also being investigated. Since antioxidant levels are different in different categories of infertile patients, these patients can benefit by antioxidant supplementation. We are conducting a clinical trial to investigate the significance of artificial sperm motility stimulants such as pentoxifylline in improving semen quality in couples with male-factor infertility and undergoing intrauterine insemination.
Center for Reproductive Medicine
The Cleveland Clinic
10681 Carnegie Avenue, X11
Cleveland, OH 44195 USA
Tel: (216) 444-9485
Fax: (216) 445-6049