Recently, researchers at Stanford University in California studied the health records of more than 40 million babies born between 2007 and 2016 and found a surprising trend when it came to children born to men who were 45 and older.
They found that overall, these children had more medical issues than those who were born to younger men. In fact, the records showed that children born to men who were 45 and older had a 14 per cent greater risk of health complications such as premature birth, low birth weight, and being admitted to neonatal intensive care.
In addition to the above complications, babies born to men in the older age bracket also scored lower on the Apgar newborn health test (a quick test performed immediately after birth that summarizes the health of the newborn), and were 18 per cent more likely to have seizures, compared to those who were born to fathers aged 25 to 34. Women were also found to have a particular pregnancy complication as well: their risk of having gestational diabetes was higher if they had children with older men.
"There are potential risks with waiting [to have children]," said Michael Eisenberg, a senior author on the report. "Men should not think that they have an unlimited runway."
Eisenberg added that while the risks were modest, the father's age should never be ignored when it comes to family planning. He did point out, however, that these increased risks were small. Taking into other considerations such as the mother's age and other factors such as education and whether she smoked, children born to men aged 45 and older were only born on average less than a day earlier, and weighed only 20 grams lighter (just over half an ounce), compared to those with younger fathers.
The reason behind these complications remains a mystery for now, but Eisenberg and his colleagues believe that the answers lie somewhere in changes in the DNA of older men's sperm. Last year, a Harvard study found that IVF births fell as fathers' ages increased, which backs up this theory.
Dr. Hilary Brown, a perinatal epidemiologist at the University of Toronto, suggested that despite the researchers' efforts, damage to DNA in older mens’ sperm was only one possible explanation for the health issues found in babies with fathers of advanced paternal age
"Studies have shown that advanced paternal age is associated with negative health behaviours such as smoking and frequent alcohol consumption, obesity, chronic disease, mental illness, and sub-fertility,” she said. She added that all of these are also linked to health problems in newborns.