By the time a man is 60 years old, sperm deterioration is so great that 85% of sperm is considered to be abnormal.

Furthermore, medical conditions such as obesity, cancer and cystic fibrosis can also impact male fertility, such as hormone deficiencies as well as genetic diseases.
Studies have found that both sperm quality and sperm mobility decrease as men age, leading to a reduced chance of conception. In addition, the natural process during which damaged sperm die and are flushed from the body slows down with age, impacting sperm quality. Sperm damage is also more common as men age.
A recent study has found that advanced age in men carries similar risks as advanced age in women with regard to passing on birth defects to their offspring as well as with reducing an individual’s chances of getting pregnant. The study was conducted over a fourteen-year period and found that were was an increased risk of Down’s syndrome in patients, particularly in cases when both the mother and father were over the age of 40.
Studies have also found that there is a link between a father’s age and the risk of schizophrenia and autism, as well as achondroplasia, a genetic disorder that often results in dwarfism. This is because sperm DNA fragmentation increases with male age, leading to a higher risk of gene mutation.
A study conducted by the University of California Berkeley in the United States also supports the relationship between male age and fertility. The study found that sperm began to deteriorate during a man’s twenties, and that sperm function, including sperm motility, slowed down 0.7% annually. By the time a man is 60 years old, sperm deterioration is so great that 85% of sperm is considered to be abnormal. The study was based on the analysis of sperm of 100 men ranging in age from 22 to 80.