Age and Male Reproduction
Men can reproduce at almost any age because they never stop making sperm. Women, on the other hand, are born with all the eggs they will ever have. This means that the eggs age as the woman ages, which can increase the risk for chromosomal abnormalities in an embryo.
Although the risk for sperm chromosomal abnormalities does not increase as men age, the potential for DNA damage does increase as men age. Sperm are produced from stem cells in the testicles that must keep dividing. In order for the cells to divide, the DNA in these cells must divide as well. Because the DNA is dividing to a larger extent, the chances for a genetic mutation occurring increase over time. Combine this with older females chances for reproductive success and the outcomes for a successful pregnancy are quite low. A study completed in 2002 found that the risk of miscarriage increased in older men but only when the women were also older.
Other Factors affecting male fertility
Because the numbers of couples observed in this study is so large, it enables researchers to come to firm conclusions. This data could be essential in the decision for couples to wait to start a family or begin sooner. This data was obtained only in IUI patients. Other research shows that in patients undergoing more invasive procedures like IVF and ICSI where sperm is injected directly into the egg, male age was not as big of a factor. While more invasive, the treatments are also more effective. The current study recommends using these treatments in couples if either the male or female is over 40.
While these methods are not guaranteed, they are the best choices for achieving pregnancy and preventing miscarriage in couples with older men.