Content note: this article contains references to miscarriage and fertility issues that readers may find upsetting.

’Tick, tock’ are words no woman wants to hear when it concerns her fertility. Whether or not you’ve decided to have children, we’re all too painfully aware of how our fertility can start to decline as we head into our 30s and 40s.

We accept that the later a woman leaves trying to conceive the harder it can become, but the same can’t be said when it comes to men. There’s increasing awareness around the so-called male menopause (or andropause) yet the existence of a male biological clock is rarely discussed. However, research shows that for women between the ages of 35 and 40, the chances of conceiving and delivering a healthy baby are significantly lower if their partner is over 40. 

So, could it be time to challenge the assumption that the burden of fertility falls to women? And if so, what implications could the male biological clock have on the way we think about fertility in general? We asked the experts.

You’d be forgiven for thinking that men can father children forever – the media is awash with stories of older dads, but according to Lily Elsner, the founder of Jack Fertility, this is a myth.

“There is indeed a male biological clock,” she tells Strong Women. “Various aspects of sperm quality and the male’s overall reproductive health start decreasing at about age 40 and consistently decreases, with this accelerating in middle age. Sperm health starts to decline around age 35 and worsens over time.”

And science agrees, with research showing that paternal age is an important factor in fertility.

“We carried out our own research into the impact of advanced paternal age on the outcomes of pregnancy following IVF treatment and found that live birth rates drop significantly when the male parent is aged 40 or above,” Professor Geeta Nargund, founder of Create Fertility and senior consultant gynaecologist and lead consultant for reproductive medicine services at St George’s Hospital, London, tells Strong Women.

“The risk of miscarriage for women whose partners are over 45 is twice as high when compared with the rates of those whose partners were under 25. While the quantity and quality of women’s eggs decrease past the age of 35, men, too, will see a drop in the quality and quantity of their sperm throughout their 40s. We must understand that the age of both parents can impact the outcome when they choose to start a family.”

We know that the female reproductive system starts to decline in our mid-30s, with our egg quality and count decreasing with age, but what causes the male decrease?

It seems that it’s a combination of age factors and lifestyle, according to Elsner.

“As a person ages, sperm quality declines due to ageing and reduced testosterone levels,” she says. “In addition, increasing rates of DNA fragmentation as part of the ageing process can also affect semen quality and therefore fertility.”

So, given that the research is pretty clear on the issue, why is there such a lack of awareness around male fertility and biological clocks?

“For far too long, there has been a commonly accepted falsehood that fertility and the biological clock are solely a woman’s issue,” says Professor Nargund. 

“In reality, around half of cases where couples are struggling to conceive involve male factor infertility and it is imperative that we change the narrative around male infertility. Men who are under the illusion that age will have no impact on their fertility health may struggle to conceive further down the line.”

But the experts are clear that this way of thinking needs to change – not least because, unlike female fertility, it’s relatively simple to improve sperm quality through lifestyle changes.

“Male fertility remains one of the last taboos in society,” says Elsner. “So much of the male identity is wrapped up in being virile and having the potential to father a child. For similar reasons, sperm has not been seen as what it is – a fantastic biomarker of overall male health. Between the ‘ick’ factor and very little scientific research, this has remained an unexamined area despite its critical importance to both men themselves and their partners and future children.”

Professor Nargund is clear that better education is fundamental to improving fertility outcomes. 

“The root of the issue is a lack of education surrounding our own fertility health and the lifestyle choices that affect it, as well as its natural declination with age,” she explains. “The conversation is all too often centred around women when the chances of successfully naturally conceiving are equally impacted by the health of the male and female counterparts.”

Images: Getty