The actor Al Pacino is having a child in his eighties. What does the science say about the impact of older fatherhood on fertility, loss in pregnancy and disease risk?
Then there’s the risk of disease after birth. It has been known since the 1950s that older fathers are more likely to have children with the genetic disorder achondroplasia. But since then, correlations with various other conditions have emerged.
“It has become increasingly clear that advanced paternal age, just like advanced maternal age, is associated with… poor health effects in offspring,” the Utah researchers write.
Researchers at Stanford University, for example, found older father were linked to increased risks of low birth weight and seizures in newborns. Advanced paternal age is also associated with increased rates of various childhood cancers, as well as congenital cardiac defects.
It is worth remembering, however, that like many studies that examine associations between health and possible causes, the mechanisms are unclear. There could be other complicating factors that play a role, such as the lifestyle of parents and environmental pollution.
Still, researchers have found that as men age, they can pick up mutations and DNA damage in the cells that form sperm that can then be passed on to the following generation.
Studies like these are leading to changes in the way doctors and scientists think about fertility more generally. There has, historically, been a tendency to focus on the woman and her age when a couple has trouble conceiving. Indeed, much of the research has focused on female fertility. But it is now becoming clear that while male fertility may decline more slowly, and later in life than in women, the age of a father still matters.
For now, the cases of Pacino and De Niro – and other men in their seventies, eighties and nineties – remain a rarity. But overall, fatherhood is no longer a young man’s game. Since the 1970s, the number of US fathers aged under 30 years has decreased by 27%, while the number of fathers aged 45-49 years increased by up to 52%.
If the current trends continue, medicine – not to mention social attitudes – will no doubt have to adapt.
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