A lost less is known about the morbidity and mortality consequences of male infertility. It was the aim of our study to analyse the association between sperm concentration and individual lifetime mortality in men. The data sources included medical records of 601 men who attended the andrological service at the Marburg University Hospital between 1949 and 1985, and vital data gathered from public registration offices and a statutory health insurance. A Cox regression model estimated a two-fold higher mortality risk for oligozoospermic men as compared to the normozoospermic group for cohorts born between 1892 and 1931. Since a selection bias could not be found, we assume there to be a connection between poor fertility status and a shorter lifespan in men. Possible explanations for the variation in mortality risk are: (i) Lifestyle and health behaviour in adulthood, (ii) conditions in utero, and (iii) genetic dispositions.