Recent advances in understanding and managing male infertility

Abstract

Infertility is a prevalent condition affecting an estimated 70 million people globally. The World Health Organization estimates that 9% of couples worldwide struggle with fertility issues and that male factor contributes to 50% of the issues. Male infertility has a variety of causes, ranging from genetic mutations to lifestyle choices to medical illnesses or medications. Recent studies examining DNA fragmentation, capacitation, and advanced paternal age have shed light on previously unknown topics. The role of conventional male reproductive surgeries aimed at improving or addressing male factor infertility, such as varicocelectomy and testicular sperm extraction, have recently been studied in an attempt to expand their narrow indications. Despite advances in the understanding of male infertility, idiopathic sperm abnormalities still account for about 30% of male infertility. With current and future efforts examining the molecular and genetic factors responsible for spermatogenesis and fertilization, we may be better able to understand etiologies of male factor infertility and thus improve outcomes for our patients.

The effects of varicocelectomy on the DNA fragmentation index and other sperm parameters: a meta-analysis

“…The prevalence of clinically relevant varicocele ranges from 5 to 20%. It has affected 19–41% of men with primary infertility and 45–81% of men with secondary infertility [ 1 – 4 ]. The higher prevalence of varicocele in men with secondary infertility than in those with primary infertility suggests that varicocele is most likely a progressive condition, rather than a static pathological condition, resulting in potential functional and structural testicular damage [ 5 ].…”

“…It is thought to be primarily related to small vessel obstruction and venous stasis in the scrotum, causing raised scrotal temperature and tissue hypoxia. This, in turn, causes germinal cell dysfunction and reduces spermatogenesis [ 4 , 6 , 7 ]. Other explanations for infertility in varicocele patients include endocrinological changes and the back flow of adrenal and renal metabolic products through the left internal spermatic vein [ 6 , 8 ].…”

CircRNA expression profile and functional analysis in testicular tissue of patients with non-obstructive azoospermia

“…Infertility is a worldwide reproductive health problem that affects an estimated 70 million people globally [1]. The world Health Organization estimate that 10–15% of couples struggle with infertility issues and male factors account for about half of all infertility cases [2, 3] Unfortunately, nearly 60–75% of male infertility is unexplained or idiopathic, since the molecular mechanisms underlying the defects remain unknown [4, 5].…”

The heat shock protein family geneHspa1lin male mice is dispensable for fertility

“…Approximately 9% of couples are affected by infertility, with male infertility thought to play a role in 50% of infertile couples estimated by the World Health Organization (WHO) (Barratt et al, 2017). Male infertility attributed to a variety of reasons including: genetic factors such as mutations (Fainberg & Kashanian, 2019;Signore et al, 2019); diseases such as testicular cancer, cryptorchidism (Skakkebaek et al, 2016); unhealthy habits such as alcohol, tobacco and drug addiction (Sansone et al, 2018); environmental stress such as intense exposure to heat, pesticides, radiation, radioactivity and other harmful substances (Durairajanayagam, Agarwal & Ong, 2015;Kesari, Agarwal & Henkel, 2018). Spermatogenesis is a precisely regulated and complex process.…”