March 7, 2026, 9:28 am | Read time: 5 minutes
Could the quality of sperm say something about a man’s life expectancy? A large-scale Danish study involving more than 78,000 men provides impressive findings. There is indeed a remarkable correlation between semen quality and mortality risk. FITBOOK editor Julia Freiberger explains exactly what the researchers from Denmark found out.
Sperm quality often only becomes an issue when the desire to have children does not work out. But apparently, there is more at stake for men—namely, their life expectancy. Find out below how much longer men with better sperm quality live compared to men with poorer quality, and how the scientists responsible determined this.
Overview
Better Sperm Quality Apparently Means a Longer Life
A new study, which analyzed data from Danish men over a period of up to 50 years, now provides reliable answers. It shows that men with the highest number of motile sperm live on average 2.7 years longer than men with severely impaired sperm quality. Particularly noteworthy: even after taking into account educational level and known pre-existing conditions, this correlation remained, albeit slightly weakened.1
Correlation Between Semen Quality and Life Expectancy Analyzed
The aim of the study was to analyze the relationship between semen quality and the life expectancy of men. Previous research had already suggested that poor semen quality could be associated with higher rates of disease and mortality. However, the extent to which existing diseases influence this relationship has not yet been comprehensively investigated.
The study is based on data from 78,284 men who underwent a semen analysis in a Danish laboratory. This happened between 1965 and 2015 and was mostly due to fertility problems within the partnership. The study recorded various semen quality parameters. These included ejaculate volume, sperm concentration, sperm motility, and the proportion of morphologically normal sperm.
Using the Danish population register, the mortality of the men was tracked over decades (up to 50 years). With an average follow-up period of 23 years and a total of 8,600 registered deaths, the study was able to examine the long-term effects of sperm quality on life expectancy in detail. Of particular importance was the question of whether health problems that existed before the sperm examination could explain the observed correlation.
Study Design and Methods
This study is a retrospective cohort study with register data. The participants were men between the ages of 18 and 65 who had a semen analysis performed in a Danish laboratory between 1965 and 2015. All men were linked to the national health registers via their unique Danish personal identifier to record deaths.
The researchers analyzed various semen quality parameters, including:
- Sperm concentration (number of sperm per milliliter of ejaculate)
- Semen volume (total amount of ejaculate)
- Motility (mobility of the sperm)
- Morphology (shape and structure of the sperm)
- Total number of motile sperm (the most important indicator in the study)
Cox regression analyses were used to investigate how sperm quality is related to overall mortality. The results were analyzed both for the total population and for a subgroup. The altter consisted of 59,657 men who provided a semen sample between 1987 and 2015. In this subgroup, educational level and known pre-existing conditions were also taken into account.
Previous studies have already indicated that poor sperm quality can be associated with an increased burden of disease and a lower life expectancy.2,3,4
Sperm Motility Is Crucial
The study revealed a clear dose-dependent relationship between sperm quality and life expectancy: the higher the number of motile sperm, the longer the men lived.
Specifically, It Showed That
- Men with more than 120 million motile sperm had an average life expectancy of 80.3 years.
- In contrast, men with 0 to 5 million motile sperm only lived for 77.6 years—a difference of 2.7 years.
- Men with azoospermia (no sperm in the ejaculate) lived an average of 78.0 years.
- Men with a very low sperm count (0 to 5 million) had a higher mortality risk than azoospermic men (they had a complete absence of sperm in the ejaculate).
Even after taking into account educational level and known pre-existing conditions, the association between sperm quality and mortality remained, albeit slightly weakened. These results show that semen quality appears to be an independent predictor of life expectancy.
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What Is the Significance of the Results?
The results illustrate that sperm quality is not only a marker of fertility, but could also provide important clues to overall health. Men with poor sperm quality could have an increased risk of chronic diseases and a lower life expectancy.
However, there is still a need for further research:
- The heterogeneous azoospermia group: the different reasons for the complete absence of sperm in this group have not been explored in more detail for a link to life expectancy.
- Possible unknown health factors: For example, unrecognized pre-existing conditions or lifestyle factors could play a role.
For medical practice, this means that sperm quality could possibly be used as a marker for general health. However, concrete preventive measures are only meaningful after further investigations.
Conclusion
The Danish long-term study shows that high semen quality appears to be associated with a longer life expectancy. Men with poor sperm quality had an increased risk of death, even after taking into account their level of education and known pre-existing conditions.
These findings could influence health care in the long term. Sperm quality could serve as an indicator of general health to identify at-risk patients at an early stage. However, further research is needed to better understand the biological mechanisms behind this connection and to develop targeted preventive measures.