The Renaissance of Male Infertility Management in the Golden Age of Andrology

Abstract

Infertility affects nearly 186 million people worldwide and the male partner is the cause in about half of the cases. Meta-regression data indicate an unexplained decline in sperm concentration and total sperm count over the last four decades, with an increasing prevalence of male infertility. This suggests an urgent need to implement further basic and clinical research in Andrology. Andrology developed as a branch of urology, gynecology, endocrinology, and, dermatology. The first scientific journal devoted to andrological sciences was founded in 1969. Since then, despite great advancements, andrology has encountered several obstacles in its growth. In fact, for cultural reasons, the male partner has often been neglected in the diagnostic and therapeutic workup of the infertile couple. Furthermore, the development of assisted reproductive techniques (ART) has driven a strong impression that this biotechnology can overcome all forms of infertility, with a common belief that having a spermatozoon from a male partner (a sort of sperm donor) is all that is needed to achieve pregnancy. However, clinical practice has shown that the quality of the male gamete is important for a successful ART outcome. Furthermore, the safety of ART has been questioned because of the high prevalence of comorbidities in the offspring of ART conceptions compared to spontaneous conceptions. These issues have paved the way for more research and a greater understanding of the mechanisms of spermatogenesis and male infertility. Consequently, numerous discoveries have been made in the field of andrology, ranging from genetics to several "omics" technologies, oxidative stress and sperm DNA fragmentation, the sixth edition of the WHO manual, artificial intelligence, management of azoospermia, fertility in cancers survivors, artificial testis, 3D printing, gene engineering, stem cells therapy for spermatogenesis, and reconstructive microsurgery and seminal microbiome. Nevertheless, as many cases of male infertility remain idiopathic, further studies are required to improve the clinical management of infertile males. A multidisciplinary strategy involving both clinicians and scientists in basic, translational, and clinical research is the core principle that will allow andrology to overcome its limits and reach further goals. This state-of-the-art article aims to present a historical review of andrology, and, particularly, male infertility, from its "Middle Ages" to its "Renaissance", a golden age of andrology.

Keywords: Andrology; Male infertility; Spermatozoa.

Fig. 1. Notable/major discoveries in the field of male infertility. Several significant discoveries have taken place in the andrological field in the last 85 years. They consist of genetics, several “omics” technologies, oxidative stress and sperm DNA fragmentation, the sixth edition of the WHO manual for semen analysis, artificial intelligence, management of azoospermia, fertility in cancer survivors, artificial testis, 3D printing, gene engineering, stem cells therapy for spermatogenesis, reconstructive microsurgery, and seminal microbiome. AZF: azoospermia factor, CFTR: cystic fibrosis transmembrane conductance regulator, NGS: next-generation sequencing, OS: oxidative stress, SDF: sperm DNA fragmentation, WHO: World Health Organization [44555657585960616263646566676869707172].