Older father, younger mother, bad idea for baby?

Children conceived by men over the age of 45 struggle in intelligence tests

The trend for men to follow in the fertile footsteps of Michael Douglas, Mick Jagger and Rupert Murdoch by becoming fathers in later life may have unforeseen and unwanted consequences for their children.

The offspring of older fathers are more likely to do less well in intelligence tests than the children of younger men, scientists say, and it may be the result of genetic problems with the sperm of men over 45. The children of older mothers, by contrast, tend to fare better in intelligence tests than children with younger mothers. The researchers believe this may be the result of better nurturing by more mature women.

It is well established that more older men are fathering children. In 1993, for instance, about 25 per cent of births within marriage in England and Wales were to fathers aged 35 to 54, but this had risen to 40 per cent by 2003.

Well-known older fathers include the Harry Potter actor Sir Michael Gambon, 68, whose partner Philippa Hart, 44, is reportedly pregnant with their second child. The BBC's world affairs editor, John Simpson, and his second wife, Dee Kruger, a television producer, had a son, Rafe, in January 2006, when Simpson was 61.

In women, it becomes increasingly difficult with age to conceive, but this is less so with men, who can father children for as long as they are capable of having sex – which can be well into their 70s or 80s. While there has been extensive coverage of the health problems associated with older motherhood, scant attention has been paid to any potential difficulties faced by the children of older men. However, recent studies have linked paternal age with congenital problems such as neural tube defects and a range of medical disorders of later life, such as schizophrenia, dyslexia, bipolar disorder and autism.

The latest study was based on a retrospective analysis of nearly 33,500 children born in America between 1959 and 1965, whose cognitive abilities were tested at the ages of eight months, four years and seven years. In addition to being assessed on hand-to-eye co-ordination, sensory discrimination and conceptual knowledge, the older children were also tested on their reading, spelling and arithmetic ability.

John McGrath, of the University of Queensland in Brisbane, Australia, who led the study published in the online Public Library of Science, said there was a clear decrease in performance linked to paternal age – something not seen in the children of older mothers. "We report, to our knowledge for the first time, that the offspring of older fathers show impairments on a range of neurocognitive tasks during infancy and childhood.

"The patterns of these findings were relatively consistent across ages and across neurocognitive domains," Professor McGrath said. "In light of secular trends to delayed fatherhood, the clinical implications of the mechanisms underlying these findings warrant closer scrutiny."

The study, however, could not shed light on whether those children catch up with their peers in later life.

Although women are born with all the cells that evolve into future egg cells, men produce new sperm cells throughout their lives. This was thought to protect against the sort of degradation of the sex cells seen in the female egg cells as they age.

Scientists now believe that as men age, their sperm are at an increased risk of picking up minor mutations that may be passed on to offspring and can affect their development. "While most of the neurocognitive differences were small at the individual level, these could have important implications from a public health perspective," Professor McGrath said.

Start your day with The Independent, sign up for daily news emails
PROMOTED VIDEO
ebooks
ebooksA year of political gossip, levity and intrigue from the sharpest pen in Westminster
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Account Manager

£20000 - £35000 per annum: Recruitment Genius: This full service social media ...

Recruitment Genius: Data Analyst - Online Marketing

£24000 - £35000 per annum: Recruitment Genius: We are 'Changemakers in retail'...

Austen Lloyd: Senior Residential Conveyancer

Very Competitive: Austen Lloyd: Senior Conveyancer - South West We are see...

Austen Lloyd: Residential / Commercial Property Solicitor

Excellent Salary: Austen Lloyd: DORSET MARKET TOWN - SENIOR PROPERTY SOLICITOR...

Day In a Page

Isis in Iraq: Yazidi girls killing themselves to escape rape and imprisonment by militants

'Jilan killed herself in the bathroom. She cut her wrists and hanged herself'

Yazidi girls killing themselves to escape rape and imprisonment
Ed Balls interview: 'If I think about the deficit when I'm playing the piano, it all goes wrong'

Ed Balls interview

'If I think about the deficit when I'm playing the piano, it all goes wrong'
He's behind you, dude!

US stars in UK panto

From David Hasselhoff to Jerry Hall
Grace Dent's Christmas Quiz: What are you – a festive curmudgeon or top of the tree?

Grace Dent's Christmas Quiz

What are you – a festive curmudgeon or top of the tree?
Nasa planning to build cloud cities in airships above Venus

Nasa planning to build cloud cities in airships above Venus

Planet’s surface is inhospitable to humans but 30 miles above it is almost perfect
Surrounded by high-rise flats is a little house filled with Lebanon’s history - clocks, rifles, frogmen’s uniforms and colonial helmets

Clocks, rifles, swords, frogmen’s uniforms

Surrounded by high-rise flats is a little house filled with Lebanon’s history
Return to Gaza: Four months on, the wounds left by Israel's bombardment have not yet healed

Four months after the bombardment, Gaza’s wounds are yet to heal

Kim Sengupta is reunited with a man whose plight mirrors the suffering of the Palestinian people
Gastric surgery: Is it really the answer to the UK's obesity epidemic?

Is gastric surgery really the answer to the UK's obesity epidemic?

Critics argue that it’s crazy to operate on healthy people just to stop them eating
Homeless Veterans appeal: Christmas charity auction Part 2 - now LIVE

Homeless Veterans appeal: Christmas charity auction

Bid on original art, or trips of a lifetime to Africa or the 'Corrie' set, and help Homeless Veterans
Pantomime rings the changes to welcome autistic theatre-goers

Autism-friendly theatre

Pantomime leads the pack in quest to welcome all
The week Hollywood got scared and had to grow up a bit

The week Hollywood got scared and had to grow up a bit

Sony suffered a chorus of disapproval after it withdrew 'The Interview', but it's not too late for it to take a stand, says Joan Smith
From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?

Panto dames: before and after

From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?
Thirties murder mystery novel is surprise runaway Christmas hit

Thirties murder mystery novel is surprise runaway Christmas hit

Booksellers say readers are turning away from dark modern thrillers and back to the golden age of crime writing
Anne-Marie Huby: 'Charities deserve the best,' says founder of JustGiving

Anne-Marie Huby: 'Charities deserve the best'

Ten million of us have used the JustGiving website to donate to good causes. Its co-founder says that being dynamic is as important as being kind
The botanist who hunts for giant trees at Kew Gardens

The man who hunts giants

A Kew Gardens botanist has found 25 new large tree species - and he's sure there are more out there