In that previous studies have suggested causal links between male fertility and malignant cancers, Michael L. Eisenberg, from Stanford University School of Medicine (California, USA), and colleagues observe that about 35% of the male human genome is involved in reproduction, and submit that "it is conceivable that other health ailments, such as cardiovascular disease, may also be linked to defects in fertility." The researchers examined data from 137,903 men (ages 50 to 71 years) without prior cardiovascular disease who were followed up for an average of 10.2 years. The team revealed that married men with no children had a 17% increased risk of dying from cardiovascular causes, as compared with married men who had children.  Compared with fathers of five or more children, married men with no children had a 21% increased risk of cardiovascular death, and those who had one child had an 11% greater risk of dying from cardiovascular causes, as compared to men with five kids or more. The researchers conclude that: “Married men who have no children have a higher risk of dying from cardiovascular disease contracted after the age of 50 than men with two or more children.”