Older dads have biological clocks too: Why being a dad later on in life can be bad for your baby

Al Pacino is a father again at 83, but men who start families in later life risk medical issues for their children. We investigate. Photo / Getty Images

When quizzed on the arrival of his seventh child, a mere 51 years after his first, actor Robert De Niro was keen to point out that at 79, he’s not even the oldest father he knows. “Al Pacino [is about to have a baby] and he’s a few years older than me. God bless him,” he said. “I’m very happy for him.”

But while De Niro may feel like a comparative whippersnapper, many of us will be pondering the wisdom of bringing a child into the world that you are unlikely to see into adulthood, let alone be able to kick a football around with.

A man has an average life expectancy of 88, and only a one in four chance of making it to 92, when Al Pacino’s latest infant will be only nine years old.

Not that this stopped Formula One boss Bernie Ecclestone, who in 2020, three months shy of his 90th birthday, fathered a baby boy.

Meanwhile, Alec Baldwin, a comparative kid at 65, has produced seven youngsters within a decade with his seemingly unstoppable, young yoga instructor wife Hilaria. His spritely image was somewhat dented by his booking in for a second hip replacement a few months after the birth of his eighth child last September.

The Brit pack of geriatric dads include rock perennial Mick Jagger, who fathered his eighth child in 2016, at the age 73; TV presenter Jon Snow, who had a baby at the age of 73 in 2021; BBC foreign correspondent John Simpson, who was 61 when his son was born in 2006, and actor Hugh Grant, who fathered five children with two mothers after the age of 50. “It’s completely knackering trying to be a young father in an old man’s body,” Grant has said.

Mick Jagger and Melanie Hamrick celebrate son Deveraux's sixth birthday. Photo / @melhamrick Instagram

Despite their ages, all these men insist they are revelling in late-life fatherhood. And more and more men are jumping aboard the older dad train.

In 2021, the average age of a first-time father in the UK was 33.7. That’s three years older than first-time mothers and, according to the Office for National Statistics, “These figures are the highest since data collection for fathers began in 1964.”

Women’s fertility tends to be strictly limited by biology. In general, most women will be infertile by the age of 45. Also, women are born with all the eggs they will ever have, whereas men make “fresh” sperm to order.

As a result, almost all the concern about older parents is focused on women, with men often believing they can go on having healthy babies pretty much forever.

Does having an older dad pose health risks for the baby?

The evidence is that there are some real risks when men embark on fatherhood over 40, let alone after 60. Some conditions thought to be solely attributable to older mothers are also linked to paternal age, including infertility and Down’s syndrome.

Plus children of older fathers are at increased risk of physical and mental conditions, including schizophrenia, bipolar disorder, autism spectrum disorder, poor social functioning and lower intelligence.

Bernie Ecclestone with his wife Fabiana Flosi and their son Ace Ecclestone in 2022 in Mogi Guacu, Brazil. Photo / Getty Images

Professor Geeta Nargund is a senior consultant gynaecologist and lead consultant for reproductive medicine services at St George’s Hospital, London, and medical director at the assisted reproduction clinic Create Fertility.

She says: “For too long the ‘biological clock’ has been viewed as purely a women’s issue. But older paternal age not only leads to a decline in fertility but can also cause an increased risk of mental health and developmental disorders in their offspring. Children born to men over 45 are over five times more likely to have an autism spectrum disorder and 13 times more likely to be diagnosed with ADHD.”

The bad news doesn’t stop there. An Israeli study found a quarter of all cases of schizophrenia were linked to older fathers and had no correlation with maternal age. The absolute number of affected cases was one in 198 offspring of 20-year-old fathers, one in 131 for those aged 30 and one in 61 for a father aged 50.

A Swedish study compared offspring born to fathers 20 to 24 years old with those who were 45 years or older and found a 24-fold increase of bipolar disorder for the older fathers.

And a 2006 study showed that children born to fathers aged 40 to 49 were almost six times more likely to develop autism than those of fathers aged under 20. What’s more, the risk extended through the generations to their grandchildren.

Yet another study of 44,175 children found that on average, having a father aged over 50 at the time of their birth was “significantly associated” with poorer performance in standard intelligence tests.

Alec Baldwin, who already had one daughter, married Hilarie Baldwin and started a baby-making factory they now have six children. Photo / Instagram

A 2018 review published in the journal Wiley Prenatal Diagnosis reported that children born to fathers over 40 were more likely to be born with skeletal abnormalities linked to faulty genes, such as Apert syndrome and the dwarfism condition achondroplasia.

The conditions are still rare, but if a father is aged 50 to 54, the chance of their child being born with achondroplasia rises from a population risk of one in 15,000 to one in 1,250.

A study conducted by the American Cancer Society has reported a “strong association” between paternal age and the development of childhood cancers.

Men older than 35 had a 63 per cent higher risk of having offspring who developed blood cancers such as leukaemia compared with those whose fathers were younger than 25.

Children of older fathers are also more at risk of breast cancer as adults. Babies of older fathers may also be more likely to be born with a cleft palate and a child of a man aged 40 is twice as likely to have a diaphragmatic hernia compared with a 20-year-old father.

Al Pacino is a dad at 83! Actor's girlfriend Noor Alfallah, 29, confirms she's given birth https://t.co/9s1dtGEkRq pic.twitter.com/9q1XW0e6dZ

— Daily Mail U.K. (@DailyMailUK) June 15, 2023

Increased risk of miscarriage and stillbirth

Men are not only less fertile with age, but their partners are less likely to have healthy pregnancies. Prof Nargund says: “The risk of miscarriage in women with male partners over 45 is twice as high as those with partners under 25.”

In a study that adjusted for maternal age, partners of men over 45 were also more likely to develop pregnancy complications such as high blood pressure, had a 48 per cent increased risk of late stillbirth and a 13 per cent increased risk of premature birth. Babies of older fathers are 19 per cent more likely to have a low birth weight.

Sperm defects increase with age

But if sperm is “freshly made”, why does a father’s age matter so much? David Miller is a reader in molecular andrology at the University of Leeds, with a special interest in male fertility. He says: “Sperm production is affected by ageing. Without question, the risk of a foetal defect will rise with age, particularly in men over 50.”

Miller explains that a woman’s egg contains mechanisms to repair sperm defects, but even eggs from younger women “may not be able to cope” with the defects in older sperm. Plus, he adds: “If a genetic mutation occurs in the sperm of younger men, it usually doesn’t get to the egg. But when the number of mutated sperm becomes greater, it becomes more likely to fertilise the egg.”

Miller points out that the risks of serious problems are “still relatively small”. In future, he says, “Better methods for selecting sperm in IVF procedures could help reduce the miscarriage rate of older women to the same rate as younger women.

The likely reason is that we were selecting for sperm with lower levels of DNA damage. The selection might also reduce the incidence of other conditions. We’ll have to wait a few years more to find out.”

He adds that there may even be benefits from sperm from older dads. “Paradoxically, telomere length – which is correlated with longevity – increases in sperm chromosomes with advancing paternal age,” he says. “So, who knows, maybe the offspring of older men will live longer lives?”

But for now, how can men mitigate their risk? Gloria Bachman is a professor of obstetrics and gynaecology and medicine at Rutgers Medical School in New Jersey. She says the risks of later parenthood mean that men should consider banking sperm before they are 35 or at least before 45.

“It’s like home or health insurance. You may not ever need these insurances, but if you do, they’re there for you.”

Prof Nargund says: “Ultimately, stories of male celebrities fathering children much later in life only reinforce the false and arguably dangerous belief that men have no biological clock. It is vital that men are aware of the impact that their age, as well as lifestyle factors, can have on their fertility, should they want a family in the future.”