Abstract 

Extraordinary advances have been achieved in the field of male infertility over the last years and several old concepts are now challenged. 

The World Health Organization (WHO) has established new reference values for semen characteristics in its 5th edition manual which are lower than those previously reported. In the field of diagnosis, novel tests for the assessment of sperm DNA integrity and oxidative stress are also available in the modern andrology laboratory. Abnormalities in the male genome characterized by damaged sperm DNA may be indicative of male subfertility regardless of normal routine semen parameters. DNA integrity testing results are predictive of reproductive outcomes. Molecular biology genetic testing now clinically available allows the identification of a significant proportion of infertile males previously misdiagnosed as idiopathic as having de novo Yq microdeletions. The presence or absence of sperm (ejaculated or retrieved) varies depending on the specific Yq microdeletion. Although no treatment exists for this genetic condition, intracytoplasmic sperm injection (ICSI) may be effective but the male offspring will inherit the same deletion as their father. Therefore, adequate counseling is mandatory for such individuals prior to initiation of fertility treatments.

Emerging evidence suggests that life-style and environmental conditions are of utmost importance in male fertility and subfertility. Oxidative stress (OS) has been shown to be detrimental for male reproductive health. Production of free radicals can be exacerbated by environmental, infectious, and lifestyle etiologies. Therapeutic measures to decrease OS include lifestyle modifications, genital infection treatment, varicocelectomy in selected cases as well as the use of vitamins and antioxidants. Modern tools for the assessment of sperm physiology in vivo demonstrated that the entire duration of the spermatogenic cycle is shorter (~60 days) than the previously suspected 70 to 80-day period. 

In the group of men with azoospermia several percutaneous and microsurgical sperm retrieval techniques are currently available. Contrary to old reports, FSH levels are not predictive of successful sperm retrieval or sterility in men with non-obstructive azoospermia (ANO). In this subgroup of patients, microsurgical testicular sperm extraction (micro-TESE) yields the best chance of sperm retrieval, and success may be optimized by surgical treatment of clinical varicoceles or by medical therapy. Finally, it is now clear that the best treatment option for infertile men with clinical varicoceles is the microsurgical vein ligation. Spontaneous conception is significantly increased after varicocelectomy, and recent data suggests that microsurgical treatment of clinical varicoceles optimize reproductive outcome of couples undergoing ICSI or micro-TESE sperm retrieval. 

I hope that this lecture will provide a better understanding of evolving concepts in the field of male infertility to gynecologists and all health professionals involved in reproductive medicine. This increased knowledge will no doubt aid in the better management and treatment of infertile males.

Male infertility current concepts for reproductive specialists