The aim of this study is to measure the inter and intra-observer reliability for the measurements of sperm DNA damage by sperm chromatin dispersion test (halosperm). The gold standard to measure sperm DNA damage is TUNEL (Terminal desoxynucleotidyl end labelling) method. However, this method is not easy to apply in routine. Therefore we investigate to analyse the inter-method reliability between sperm chromatin dispersion test and TUNEL.