After many similar studies, it has been determined that men too have biological time clocks and that the older the father is, the more likely are the problems to occur.

As years go by and men get older their sperm changes and quality decreases, which may in return lead to specific birth defects and abnormal pregnancies.

Today, men and women decide to rise up families much later than they used to. There is a 40% increase in birth rates in men over 35 and 20% decrease in men under 30. The raising age has been linked to some reproductive problems like sponatinous abortions, and genetic diseases like achondroplasia, a type of dwarfism, and Apert syndrome, which involves severe bone malformations.

Researchers used techniques that detect DNA and chromosomal defects directly in sperm cells and they tested the sperm of 97 healthy nonsmokers, ages 22 to 80. It was found that men over 40 had twice as much sperm DNA fragmentation linked to fertility problems and sustained pregnancy.

However, not all birth defects have been linked to low sperm quality. For example, Down syndrome was not connected to the aging sperm.
There are also other factors that play a big role in reproduction abnormalities like economic status, ethnic background and nutrition. All of these factors may or may not attribute to aging and may or may not reflect on sperm quality.

While sperm motility was associated with increased DNA fragmentation, other factors like sperm concentrations, total sperm count and sperm quality were not associated with any genomic defects.