“For all types of measured semen parameters, we saw a dose-response association to mortality — the better the semen quality and quantity, the longer life expectancy,” says Laerke Priskorn, PhD, a coauthor of the study and an epidemiologist with the department of growth and reproduction at Copenhagen University Hospital in Rigshospitalet, Denmark.
“This association remained when we took into account the men’s educational level and their health status prior to semen quality assessment, which were possible factors that we thought might to some degree explain the observed association — but they did not,” says Dr. Priskorn.
Low-Quality Sperm May Be a ‘Canary in the Coal Mine’
Priskorn and collaborators examined data on 78,284 men in Copenhagen who were being evaluated for infertility and had their semen quality examined between 1965 and 2015. Semen quality was determined by measuring semen volume, sperm shape and concentration, and the proportion of sperm that were motile (capable of moving or swimming properly).
Over a follow-up of up to 50 years, 8,600 deaths occurred.
Analysis revealed that men with a total count of more than 120 million moving sperm had a 2.7-year longer life expectancy than men with a total count between 0 to 5 million.
The results, published in the journal Human Reproduction, showed that the higher-count group could expect to live to 80.3 years, compared with 77.6 years for men in the lower-count group.
The association between high quality sperm and longevity held true in a subgroup of nearly 60,000 men who provided information on any disease diagnoses they may have had prior to semen sampling.
The authors concluded that semen quality may be a universal biomarker of morbidity (having a disease) and mortality.
Joshua Bodie, MD, a urologist and an associate professor with the University of Minnesota in Minneapolis, calls male infertility a “canary in the coal mine,” signaling potential health troubles.
“There are many health issues that can affect sperm count — genetic problems, cystic fibrosis, diabetes, cancers, pituitary gland issues, and congenital conditions,” says Dr. Bodie, who was not involved in the study. “Low or zero sperm count can also be sequelae [a consequence] from sexually transmitted infections like gonorrhea or chlamydia.”
Limitations of Sperm to Assess Health
He cautions, however, that the study is observational and based on preexisting data, so the findings “need to be interpreted with caution.” Additionally, he warns against using sperm as a means to gauge the status of a man’s health.
“The predictive power of a sperm assessment is likely to be much less than other known measures, such as blood pressure, weight, fasting lipids [cholesterol levels], and blood sugar,” says Dr. Amory, who was not involved in the study.
While the study authors do not suggest that men routinely have their semen quality measured to assess general health status, they do urge men who have semen quality assessed due to fertility issues to consider potential health troubles related to low-quality sperm.
“Fertility workups, which most often occur at a young age, may provide a ‘window of opportunity’ for clinicians to identify and mitigate potential health risks that may otherwise go unnoticed until they manifest with clear symptoms,” says Priskorn.
What Impacts Sperm Quality?
Oxidative stress is an imbalance in the body of unstable molecules called free radicals and antioxidants. Antioxidants protect cells from damage caused by free radicals. Oxidative stress is known to be involved in the aging process, and could influence semen quality, according to Dr. Aitken.
To help reduce oxidative stress and improve sperm quality, Amory advises men to avoid tobacco, limit alcohol consumption, eat healthy, exercise regularly, and get adequate sleep.
“If sperm count is checked and low, take this as a warning to investigate your health and work with your physicians to try to improve your health as best as possible,” says Bodie.