A new study by the Colorado Center for Reproductive Medicine (CCRM) has found that male age does matter when it comes to having a family. This is significant for men that are waiting until later in life to have children since their age could impact their fertility and the health of their offspring. The study findings were presented by CCRM Scientific Director Mandy Katz-Jaffe, PhD, at the European Society of Human Reproduction and Embryology Annual Meeting in June.


In a controlled study, proven fertile male mice were followed during their natural lifetimes and mated monthly with young females to monitor reproductive potential. At 15 months of age (equivalent to a 45-50 year old human), only one of the thirteen males was able to father a viable pregnancy. With the utilization of next-generation sequencing, each male’s sperm was DNA sequenced comparing the young DNA sequence to the old DNA sequence of the same individual males. Our results revealed the generation over time of single base pair mutations in key genes involved in the production of sperm and development with natural male aging.

“In order to help a patient clinically, we need to first know what the problem is. We’ve suspected that men have a biological clock, like women, and that their fertility decreases with age, but we didn’t realize how this was occurring,” says Dr. Katz-Jaffe. “This new study gives us valuable information about the genetic make-up of aging sperm and is a critical step in determining how and why male fertility declines with age.”

For years, CCRM has been closely studying the role of aging sperm in fertility in conjunction with the National Foundation for Fertility Research (NFFR), a non-profit organization committed to research in reproductive medicine. Amongst other findings, these researchers have found that sperm from middle-aged and older male mice is less likely to lead to a successful in vitro fertilization (IVF) pregnancy and healthy births.

“In nearly one-third of cases, problems with male fertility impact a couple’s ability to conceive,” says William Schoolcraft, M.D., medical director of CCRM. “The better we understand how and why this is happening, the more we’ll be able to help these couples in the future have a healthy baby.”

Source: PR Newswire