Older fathers are more likely to have children with mental health problems and academic difficulties, a new study suggests.
Children fathered by a 45-year-old father or older are three times more likely to have autism, 25 times more likely to suffer from bipolar disorder and their chances of having schizophrenia are two times greater, according to the research.
Children with older fathers were also more likely to attempt suicide or have a substance problem.
The study, published online in JAMA Psychiatry, used data from more than 2.6 million Swedes born from 1973-2001.
Scientists suggest the risks may increase with advancing age because sperm are continually produced throughout men's lives and mutations may occur each time cells divide to create new sperm.
“The message to men is, if you’re in a position to do so, have your children sooner rather than later. Think when you want them and then take off a few years,” Allan Pacey, a senior lecturer in andrology at the University of Sheffield, told The Times.