['To study whether the telomere structure of germ cells from idiopathic infertile men is altered and if this impairment is influenced by meiotic recombination and telomere length.', 'We performed a detailed analysis of both telomeric repeat-containing RNA (TERRA) and telomerase distribution in testis cell spreads by combining immunofluorescence and RNA fluorescent in situ hybridization. In addition we analyzed meiotic recombination between homologous chromosomes by immunofluorescence and telomere length by quantitative fluorescent in situ hybridization.', 'University.', 'Men consulting for fertility problems.', 'Unilateral testicular biopsies.', 'We observed that TERRA levels and its nuclear distribution were compromised in infertile patients. In addition, the presence of the protein component of telomerase at telomeres decreased in the affected patients. However, neither telomerase-TERRA association nor telomere length was altered in spermatocytes I of infertile samples compared with control individuals. In addition, we observed that meiotic recombination was reduced in infertile individuals.', 'Telomere homeostasis is impaired in infertile patients, and this was translated into a decrease in TERRA levels together with an alteration of the TERRA-protein component of telomerase telomeric association in primary spermatocytes.'] Is telomere homeostasis compromised in spermatocytes from patients with idiopathic infertility?