Older fathers include Simon Cowell, whose son Eric was born in 2014 when he was 54
It is not only women who face the ticking of their biological clock.
Men who try to have a child in their fifties are a third less likely to conceive than younger men, a study suggests.
Experts now believe when women hit the menopause, at the average age of 51, men see a similar decline in their sperm quality.
Researchers tracked more than 4,200 men trying to have a baby through IVF.
They found men aged 51 and older were 34 per cent less likely to conceive than those under 35.
Although there are many ageing celebrity fathers, from Rod Stewart to Mick Jagger, the evidence suggests sperm DNA becomes damaged with age.
This may explain the higher risk of older men having children with autism and schizophrenia, and suggests women may be better off choosing a man under 50 if they want a child.
Dr Guy Morris, the research fellow who led the study from University College London, said: ‘Men’s sperm seems to be unaffected by their age right up to the age of 50, which is when there is a significant decline.
‘In women, they lose the function of their reproductive organs when they go through the menopause.
‘In men, the quality and quantity of sperm production declines with age and this seems to have a significant effect after the age of 50.’
Older fathers in showbusiness include Simon Cowell, whose son Eric was born in 2014 when he was 54, Frank Skinner, whose son Buzz Cody was born in 2012 when he was 55 and Rod Stewart, who was 66 when his eighth child, Aiden, was born in 2011.
These cases are feared to further the ‘myth’ that men can put off having a child until middle age.
Researchers analysed the records of 4,271 men having IVF at the Centre for Reproductive and Genetic Health (CRGH) in London between 2009 and last year.
They found the pregnancy rate fell as men got older, with almost half of under-35s achieving success but only 35.2 per cent of men aged 41 to 45.
Sir Mick Jagger, famous for his time in The Rolling Stones, gave birth to his eighth child at the age of 73 in 2016
Men who try to have a child in their fifties are a third less likely to conceive than younger men, a study of men having a baby with IVF suggests. Stock photo
The pregnancy rate in partners of men aged 46 to 50 fell to 32.8 per cent and hit just 30.5 per cent for men aged 51.
When women’s ages were taken into account, the slump in pregnancy chances was most significant for men aged 51.
Men of this age and older were 34 per cent less likely to be successful in IVF than under-35s, showing the fertility of men this age falls significantly.
Dr Morris, who also works at CRGH, said: ‘There may well be a public perception that male fertility is independent of age.
‘Stories of celebrity men fathering children into their sixties may give a skewed perspective on the potential risks of delaying fatherhood.’
Dr Morris, who presented the findings at the annual meeting of the European Society of Human Reproduction and Embryology in Vienna, added: ‘In the context of this emerging evidence for the deleterious effect of increasing paternal age, our data certainly support the importance of educating men about their fertility and the risks of delaying fatherhood.’
A previous study, from Beth Israel Deaconess Medical Centre in Boston, found men aged 40 to 42 were a fifth less likely to have a baby than before their 30th birthday.
While women are born with a limited supply of eggs, men make sperm throughout their lives.
The repeated cell divisions needed to do this can introduce rising numbers of errors into the sperm’s DNA, which make it less able to fertilise an egg.
The study found only 42 per cent of men over 51 have normal quality sperm, compared to 61 per cent of those under that age.
There is currently no age limit for IVF in men, although health watchdog NICE advises 42 as the cut-off for women having fertility treatment on the NHS.
Dr Jane Stewart, chair of the British Fertility Society, said: ‘When people see ageing celebrities such as Rod Stewart becoming fathers, it is easy to assume that older men are just as fertile as their young counterparts.
‘We know this isn’t strictly true – male fertility does decline with age.
‘This study is interesting because it is looking at the impact of a man’s age on IVF success, not just on the chances of becoming pregnant without IVF.’
Professor Adam Balen, co-chair of the British Fertility Society Fertility Education Initiative said: ‘We want to see fertility taught as part of the RSE (relationships and sex education) curriculum and have been successful in getting it included.
‘Young men need this information – they need to know that they won’t necessarily remain fertile their whole life and are more likely to have problems as they age.’
ARE WOMEN LESS LIKELY TO CONCEIVE WHEN THEY ARE OLDER?
The fertility of women declines as they get older – but the impact of men’s age on fertility is not so clear.
How men and women’s fertility is expected to change with age
The success of pregnancy at any given age is not unaminous, but there are estimations based on research.
The NHS states that fertility drops the most in the mid 30s.
According to one study cited by the NHS, among couples having regular unprotected sex:
- aged 19 to 26 – 92 per cent will conceive after one year and 98 per cent after two years
- aged 35 to 39 – 82 per cent will conceive after one year and 90 per cent after two years
Other data shows that aged between 25 and 27 attempting to get pregnant across 12 cycles have a success rate of around 80 per cent.
In contrast, the figure is closer to the 50 per cent mark for those aged between 40 and 45.
This is according two studies, one in 2017 led by Boston University School of Public Health, published in the American Journal of Obstetrics and Gynecology, and another led by Princeton University in 1986, published in Science.
By age 51 when women have their menopause they have about 1,000 immature eggs – compared to two million at birth – but these are not fertile, according to the British Fertility Society.
The success of IVF also depends on age, as well as what the cause of infertility is. According to the NHS, the percentage of IVF treatments that result in a live birth is 29 per cent for women under 35. But for those aged over 44, it’s just two per cent. This is why IVF is not recommended over the age of 42.
Because the fertility of women declines, many women who want children want to know at what age they should try to get pregnant to have a good chance of having the family they want.
The British Fertility Society have a chart of when a woman would need to start trying to get pregnant to have the number of children she wanted:
|Chance of meeting family size goal||1 child||2 children||3 children|
|Without IVF||50%||41 years||38 years||35 years|
|75%||37 years||34 years||31 years|
|90%||32 years||27 years||23 years|
|With IVF||50%||42 years||39 years||36 years|
|75%||39 years||35 years||33 years|
|90%||35 years||31 years||28 years|