Women aren't the only ones with ticking biological clocks. There's growing evidence that children of aging fathers face increased risk of many diseases and even premature death. But the good news is that there are ways to reduce this risk.

The most starting finding: Children fathered by middle-aged men (45 or over) are nearly twice as likely to die before adulthood. This comes from a 2008 study of about 100,000 Danish children born between 1980 and 1996.

Even after adjusting for the mother's age and other factors, researchers found an increased risk of death for children of older fathers. The mortality rate for children of men 45 and older was almost double that of children fathered by men in their late 20s. Children of teenage fathers also had higher mortality rates, but that was blamed on other factors such as poverty and the risks of teen motherhood.

Birth defects and injuries were leading causes of the greater mortality in the older men's children. The researchers speculated that the injuries may be related to conditions such as autism, schizophrenia or epilepsy. The study was published in the European Journal of Epidemiology.

As men age, fertility declines because the quantity and genetic quality of sperm decreases. In recent years, scientists have linked aging sperm to higher risk of diseases in offspring including Down syndrome, certain other congenital disorders, autism, schizophrenia, epilepsy and possibly cancer, Alzheimer's disease, multiple sclerosis and type 1 diabetes.