The WHO estimates that in 50% of couples with infertility issues, the male factor isolated is found in 30% of cases and in combination with female factors in 20%. [1][2][3][4][5] In the last decades, several studies have described a substantial decline in sperm counts, namely one systematic review that claimed a decrease of 50-60% (1973-2011). 3 In fact, over 90% of male infertility is due to poor sperm quality, low sperm counts, or these two concomitantly. 2 Various conditions can account for male infertility, namely anatomical defects, genetic abnormalities, systemic diseases, infections, gonadotoxins, and trauma, among others. 5 Among genetic causes, chromosomal abnormalities can deteriorate testicular function, and Y chromosome microdeletions are responsible for isolated spermatogenic defects. 3 Some childhood events (testicular trauma or torsion) or congenital defects like cryptorchidism may also contribute to the fertility issue. 3 Varicocele is one of the main causes, being present in 40% of infertile men. 1,3,6 Nevertheless, the literature reports a significant number of cases in which no cause is identified, ranging from 30 to 40%, and thus classified as idiopathic. 1,5 Oxidative stress affects 37 million infertile men. 3 Exposure to environmental chemicals and toxic consumption
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