There’s a wealth of medical literature that describes how the health of the egg is altered as a woman ages but there’s a growing body of evidence that a man’s sperm suffers the consequences of aging, too. The findings of a recent meta-analysis of studies of sperm quality and paternal age suggest DNA quality within the sperm is compromised as men age. This finding could help explain why pregnancy complications and miscarriage are more likely when the father is older and why the children of older fathers are at greater risk for disorders that include schizophrenia, epilepsy, Down syndrome, and autism than children born to younger fathers.
At the University of Otago in New Zealand, Dr. Sheri Johnson led a team of researchers through a study that identified diminished sperm quality in older men. A meta-analysis involves collecting and collating relevant data from many studies and then analyzing the data for a common theme which, in this case, was sperm quality in older men.
The Johnson study did not seek to determine how fast sperm quality declines with age but previous studies indicate that some characteristics of sperm quality begin to decline at around age 35 while other studies indicate other characteristics decline after age 40.
Sperm quality is typically determined by measuring sperm count and concentration and semen volume. Johnson’s study revealed fragmentation of DNA strands within the sperm that hinders fertility and health of offspring. According to Johnson’s findings, DNA fragmentation increases as a man ages. When all characteristics of sperm quality are taken into consideration, including DNA fragmentation, Johnson envisions more effective treatments for aging men seeking fertility treatment.
“Increasing male age may be an overlooked component of couple infertility, leading to our increased use and dependency on fertility treatments, such as IVF,” said Professor Neil Gemmell, a co-author of the Johnson paper. A growing number of couples choose to delay the start of their family until career goals and financial milestones have been achieved. In many cases, they turn to assisted reproductive technologies (ARTs) when conception doesn’t occur as anticipated.
Many ARTs focus on female fertility issues, especially when a man’s semen volume, sperm count, and sperm concentration fall within normal ranges. The Otago paper suggests the need to also consider the quality of the DNA within the sperm as a factor.
Men of advancing age who want to be fathers might benefit from adding vitamins and other micronutrients to their diets, according to Andy Wyrobek. Wyrobek led a study at the US Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) that found men age 44 and older who regularly consumed at least the recommended dietary allowance of vitamin C, vitamin E, folate, and zinc had sperm quality similar to that of men much younger. Men 44 and older who did not consume these vital nutrients had a much higher rate of DNA damage in their sperm. Wyrobek suggests an improved diet may help increase the chance of fatherhood for older men struggling with fertility issues.
Sources:
- University of Otago. “New Otago study confirms that sperm quality decreases with age.” University of Otago. University of Otago. 1 Dec. 2014. Web. 12 Dec. 2014.
- Krotz, Dan. “Nutrition Tied to Improved Sperm DNA Quality in Older Men.” Berkeley Lab. US Department of Energy. 27 Aug. 2012. Web. 12 Dec. 2014.