Why men should also be thinking about their biological clocks
Women are often reminded that their fertility declines after a certain age, but what about men? Liz Connor talks to some experts
Women have long been reminded of the so-called 'ticking time bomb' they face when it comes to fertility. The curse of the biological clock suggests that a woman has an innate mechanism that's counting down the time until she can no longer naturally conceive.
But what about men? We may not see as many headlines on the topic of male fertility, but experts are warning that they should be aware of possible issues, too.
Men, in theory, produce sperm throughout their entire lives (unlike women, who have a limit on their egg reserves), but that doesn't mean that they'll necessarily have the same fertility success at any age.
In fact, many men may be woefully ignorant of potential changes to their sperm and this can often catch couples out - with many falsely believing that fertility issues are most likely to automatically lie with the woman.
Infertility symptoms in men can be very vague too or come as a total shock, so may go unnoticed until a couple tries to conceive.
But do men really experience the 'tick-tock' of the biological clock in the same way as women, and should they really be worried about it?
What a fertility expert has to say...
"The importance of the age at which one has a child is well known in females but is not often taken into account for men," says Dr Victoria Walker, a fertility expert at Institut Marques (institutomarques.com). "Nevertheless, men do also have a biological clock - and it's something that they should be concerned about.
"Men produce sperm cells throughout their life, but with the passage of time, the quality of the sperm will change, reducing the fertilising capacity of semen."
Walker says that, as well as infertility, increase in age can also be linked with damage to the genetic material in sperm, which can sometimes lead to genetic disorders in babies.
Studies have supported the theory that it's not just women who matter in the middle-aged infertility equation. In a 2003 study published in the journal Fertility and Sterility, just a quarter (25%) of men over 50 were able to get pregnant with their partners within the space of a year.
A 2017 study by Harvard researchers also made recent headlines, when it found that sperm from men aged 40-42 was 46% less likely to impregnate women under 30, than sperm from men aged 30-35.
"Poor semen quality does not necessarily mean that a man won't be able to conceive," says Walker - but she notes it can hamper their chances.
It's not the only obstacle men face in this context, either. A Baylor College of Medicine review found that the chance of a baby having any of 86 congenital problems, such as Down's syndrome or spina bifida, are one in 50 on average, but rise to one in 42 when the father is over 40.
Research published in Nature also found that dads pass on more genetic mutations as they get older, and that the rising age of fatherhood could be a factor in increased rates of conditions such as schizophrenia and autism.
What causes a decline in sperm in older men?
The decline in male semen quality - which includes both sperm count and the overall quality of the sperm - has been a topic of discussion among the scientific community for many years.
"Previous studies have shown that in the 50 years up until 1990, sperm count declined by 1% per year," says Walker.
"Since then, numerous published papers have discussed this subject, and many researchers agree that there is a geographical element to sperm count, with poorer semen quality typically seen in more industrialised countries.
"We've been investigating this topic for many years at Institut Marques, and the decline in male fertility may be a consequence of environmental contaminants, such as petrochemical agents," she adds.
Petrochemicals are chemical compounds which can be made from oil, natural gas and coal and are found in a wide array of household items, from lunch boxes and bin bags to plastic bottles.
"As well as polluting the environment, persistent organic pollutants (POP) can dissolve into human fat, a phenomenon known as 'lipophilicity'," explains Walker. "When dissolved into fat, some POPs act as estrogenic endocrine disruptors, which means they behave in the same way as female hormones, even if they're in males."
Endocrine disruptors have been associated with possibly altering functions of the endocrine system and interfering with sperm count and quality. Dr Walker says they can also increase oestrogen levels in pregnant women, which can, in turn, affect foetal development - in relation to early male development, this may have an early impact on how the testicles develop and their later ability to produce sperm.
Can your lifestyle affect your fertility?
While Walker believes there is nothing a man can do to slow the overall biological clock - as everyone naturally ages - there are lifestyle factors that are believed to help improve semen quality.
Rob Hobson, head of nutrition at Healthspan (healthspan.co.uk), explains that lifestyle can often be at the root of a man's inability to conceive.
"Issues including stress, depression and anxiety can be responsible for mood swings, irritability, lower libido and a general lack of enthusiasm," says Hobson.
"These can be amplified later in life as a result of lifestyle pressures, such as work, relationships, divorce, money problems, pressure to support family or worries over ageing parents."
He notes that lifestyle factors such as smoking, drinking, stress and diet are a common denominator in the aetiology of male infertility, while diabetes is considered to be one of the leading causes of male impotence.
"Men looking to start a family should definitely quit smoking, curb their drinking and seek to manage their stress in order to promote the production of healthy sperm," advises Hobson. "Adopting a healthy balanced diet that includes plenty of nutrients can also help insure the production of male sex hormones.
"Zinc is required in higher amounts in men than women, as it helps with the production of male sex hormones," he says, advising men to load up on seafood, poultry, nuts, seeds, beans, eggs and whole grains.
"Vitamin C is also important, as it helps to prevent sperm cells from clumping together, which is common with infertility," notes Hobson. "Most men get enough vitamin C in their diet, but you can ensure your intake by eating plenty of fruits and vegetables such as red peppers, berries, citrus fruits and green vegetables, which are particularly high in this vitamin.
"Eating more plant-based foods - vegetables, beans, pulses and lentils - will increase your intake of antioxidants that help to reduce the damage caused by excess free radicals, considered by some to be a contributory factor leading to infertility in men," he adds.
While leading a healthier lifestyle is always a good idea, it's good to note that some men are just plain lucky when it comes to the genetic lottery. Fertility is not a one-size-fits-all issue, and countless celebrities and rock stars have fathered children beyond the age of 60, like Mick Jagger, Ronnie Wood and Jeff Goldblum.
The bottom line? The biological clock probably isn't something that anybody in their prime should lose sleep over - but everybody should be aware that men can experience fertility issues, just as women can too.
If you're hoping to conceive in the future, having an awareness that age may be a factor, alongside adopting a balanced healthy lifestyle, is a good bet.
If you're concerned, or already trying to conceive and struggling, it's always worth speaking to your GP or a specialist, who can help you to get to the bottom of any fertility issues.