Abstract / Summary
Background: Male infertility is a serious health problem globally, and there is growing evidence that inflammation and immune dysregulation are involved in its pathogenesis. Interleukin (IL)-40 and IL-41 are cytokines whose involvement in male infertility remains poorly known. Objective: To investigate the potential role of serum IL-40 and IL-41 in male infertility by comparing serum levels of these ILs in infertile male patients and healthy controls and assessing their associations with clinical and laboratory parameters.Materials and Methods: This case-control study was conducted at Kamal Al Samarrai Hospital for Infertility and In Vitro Fertilization Infants in Baghdad, Iraq, from October 2025 to January 2026. The study group included 70 infertile men and 20 fertile controls. Serum IL-40 and IL-41 levels were measured by enzyme-linked immunosorbent assay (ELISA). Results: Serum IL-40 levels were significantly higher (P-value = 0.001) in infertile male patients than in the control group. In contrast, IL-41 levels did not differ significantly between the two groups (P-value = 0.281). Receiver operating characteristic (ROC) analysis showed satisfactory diagnostic performance for IL-40 (AUC = 0.810, P-value < 0.001), whereas IL-41 showed limited discriminative ability (AUC = 0.580, P-value = 0.373). Conclusions: These findings suggest that serum IL-40 is a promising immunological biomarker for male infertility, whereas IL-41 appears to have limited diagnostic value. Further large-scale multicenter studies are required to validate these findings.