Paternal age and sperm DNA fragmentation index (DFI) have become significant determinants of male infertility and assisted reproductive technology (ART) success rate. This article aims to establish the relationship between increased DFI and advanced paternal age and the developmental potential of embryos where intracytoplasmic sperm injection (ICSI) has been used. Sperm DNA integrity was measured on 150 participants aged 25–55 using the sperm chromatin dispersion (SCD) assay; DFI levels were further classified into subclinical, transition, and clinical abnormality ranges. Analysis of the findings showed a positive relationship between the age of the father and DFI (r = 0.475, p < 0.001), and older men had notably higher scores of DFI. In turn, DFI at the alternative level was negatively correlated with fertilization rates (r = -0.416, p < 0.001) and the quality of embryos on days 1 and 3 after ICSI. The results outlined the role of sperm DNA fragmentation when it comes to the success rate of ART, especially for patients of advanced age. Clinical relevance focuses on DFI testing and individual treatments that improve sperm selection [intracytoplasmic morphologically selected sperm injection (IMSI), physiological intracytoplasmic sperm injection (PICSI)] and antioxidants due to age-associated oxidative damage. In this way, the study solves the research gap on the connection between paternal age, DFI, and ART success, which can help improve reproductive satisfaction and patient education on potential risks associated with delayed fatherhood. Subsequent studies must confirm the results and investigate new approaches to enhance ART outcomes in males with high DFI. © The Author(s). 2026 Open Access. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (https://creativecommons.org/licenses/by-nc/4.0/). This license permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited, a link to the license is included, and any changes are indicated.