For decades, fertility has been told as an exclusively female story. The famous case of ‘Papuchi’, a father at 90, helped reinforce the idea that men could wait without consequences.
But today, science dismantles that narrative: the male biological clock exists, and its effects can no longer be ignored.
From viral symbol to questioned myth
Twenty years ago, the birth of Julio Iglesias Puga’s posthumous daughter turned ‘Papuchi’ into an icon of late fatherhood. His story swept across Spain and beyond as proof that age was not a problem for men.
Two decades later, however, that case is viewed in a different light.
The scientific evidence accumulated in recent years has shifted the focus: yes, men produce sperm throughout life, but that does not mean they maintain the same quality. Over time, sperm also ages.
And that detail changes everything.
What happens to sperm with age (and why it matters)
Far from being a minor factor, paternal age directly influences several key aspects of reproduction. The major scientific societies, such as the American Society for Reproductive Medicine, already consider it a fundamental element in fertility assessment.
Among the most relevant effects are:
- Progressive decline in semen quality
- Greater fragmentation of sperm DNA
- Lower probability of achieving pregnancy (natural or assisted)
- Increased risk of miscarriage
- Higher likelihood of genetic mutations and some neurodevelopmental disorders
As specialist Juan José Fraire-Zamora explains, “for years it has been taught that male fertility barely changes, but today we know that aging also affects sperm and can influence the entire reproductive process.”
That is, it’s not only about conceiving, but what happens after.
The data that changes the story: even with young donor eggs
One of the most revealing findings comes from a study presented in 2025 by the Eugin group at the European ESHRE conference. It analyzed more than 1,700 in vitro fertilization cycles with a key detail: all used eggs from young donors.
The objective? To remove the woman’s age factor and observe only the male impact.
The results were clear:
- In men over 45, the miscarriage risk rose to 23.8%
- In those under 45, it stayed at 16.3%
- Birth rates also fell: from 41% to 35.1%
That is, even under optimal conditions, the father’s age continues to make a difference.
Today it is estimated that up to 50% of reproductive problems have a male component. However, social perception remains anchored in the past.
In a context where more and more people delay motherhood and fatherhood, this paradigm shift is key.
Experts insist that this is not about alarming or setting a “deadline,” but about understanding that fertility is a two-person issue. Being informed, planning, and consulting in a timely manner can make a difference.
Twenty years after “Papuchi,” the conclusion is clear: the biological clock was never exclusively female.
