The main goal of this study is to investigate the correlation between sperm head vacuole areas and sperm aneuploidy rates in men with isolated teratozoospermia or OAT. Vacuole areas will be measured by MSOME and aneuploidy rates by FISH for chromosomes 18, X and Y. Moreover, the correlation between sperm head vacuole areas and other nuclear alterations (DNA fragmentation, abnormal chromatin condensation, telomere abnormalities) will be evaluated. Semen samples from 200 patients recruited over a 2-year period will be collected, stored and analyzed.