A study from Stanford University in the USA reports that babies of older fathers may be more likely to have health problems. Scientists studied data on 40,529,905 births in the USA between 2007 and 2016 to ascertain whether a father's age adversely affects his child's health. Researchers discovered that compared to babies born to fathers in the 25-to-34 age bracket, babies born to fathers over the age of 45 were at greater risk of being born with health problems. These included being born prematurely, having a low birth wieight or being admitted to a neonatal intensive care unit. The researchers added that babies born to older fathers were generally not as healthy as those conceived by younger fathers.

One scientist said a lot more detailed research was needed to prove that older fathers conceive less-healthy babies. Dr Michael Eisenberg from the Stanford University School of Medicine said: "I think it's important to understand that the risks we are seeing are modest. So for an individual, the risk may not change much." He added that his team's data could show a trend that health departments in governments might want to be aware of. He said: "At a population level, there may be public health implications of men...waiting longer to conceive." Dr Eisenberg concluded that: "While the oldest father ever is 96, this research suggests that the risk to child and mother may increase if fathers conceive later."