The effects of male age on sperm DNA damage: An evaluation 2,178 semen samples

Abstract

Objective: This study aimed to evaluate the effects of male age on sperm DNA damage. Methods: This cross-sectional study included semen samples collected from 2,178 men seen at an infertility clinic. For DNA integrity analysis, the proportions of spermatozoa showing DNA fragmentation (TUNEL assay), abnormal chromatin packaging/underprotamination (chro-momycin A3), abnormal mitochondrial membrane potential (MMP/MitoTracker Green), and apoptosis (annexin V) were recorded. For group comparisons, enrolled subjects were divided into three groups based on their ages: ≤35 years; 36-44 years; and ≥45 years. The associations between age and sperm parameters were assessed using Spearman's rank correlation coefficient. Results: Although aging did not affect sperm apoptosis (p>.05), sperm DNA fragmentation and MMP deteriorated significantly with age (p