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The regulation of the endocrine and reproductive function of the testis is under the concerted action of gonadotropin-releasing hormone (GnRH) and gonadotropins, such as luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
Male infertility is a highly heterogeneous, multifactorial, complex pathology of the reproductive system, affecting approximately 7% of the general male population. Genetic factors are estimated to contribute to nearly 20–25% of severe male infertility cases and inversely correlate with sperm production . In fact, their frequency is 0.4% of the general population, while patients with a spermatozoa count of less than 5 million/ml already show a 10-fold higher incidence (4%) .