Infertility has for far too long been treated as an all-female issue. Yet in about half of the cases for the one in six couples in this country who are experiencing problems conceiving, it is the man’s infertility that is the problem. So why is it in my fertility clinic practices – both NHS and private – I meet men every week who have no idea of the vital role their age and lifestyle choices will play in whether they and their partner can have a healthy baby.

Reports about celebrity fathers in their 50s, 60s and older, have blinded many men to the reality that they, too, have a biological clock. For every Ronnie Wood or Rupert Murdoch fathering a child in their 60s or 70s, there are many, many more men like the barrister who came to me, a widower with grownup children who was desperate to start a new chapter in life.

He and his new partner were very much in love and planned to have a baby, but after trying unsuccessfully, fertility tests revealed that his sperm quality and quantity had already declined and that it was too late for natural conception. As a result, his wife had to undergo IVF treatment, despite the fact that she did not have a fertility issue herself. Having tried treatment, the couple eventually gave up on the idea of having a child together.

The headlines don’t tell the real story: the likelihood that fertility treatment may have played a role. The concept of the ticking biological clock is a well-worn cliche when applied to women, but men need to wake up to their own clock.

Advancing paternal age is linked with an increased risk of psychiatric and academic morbidity. Scientific papers underline that, from the age of 40, and especially from the age of 45, the quantity and quality of a man’s sperm decline. In this age range we see an increasing number of genetic mutations in sperm. This means it takes longer for a man and his partner to conceive, and there is a higher chance of miscarriage. The actual figures come as a great shock to many men. It can take five times as long to conceive where a woman has a male partner over 45, and the risk of miscarriage is twice as high in women with male partners over 45 compared to those with partners under 25.

There is also a greater risk of conditions that include dwarfism, while children born to men over 45 are five times more likely to have an autism spectrum disorder and 13 times more likely to be diagnosed with ADHD.

We need to break down the silence, improve education and give men the opportunity to open up and discuss a topic that can be as painful for them as it is for their female partners.

Outside of the effect of age on fertility, men must understand the role played by lifestyle choices. Smoking, excessive alcohol intake, using recreational drugs, poor diet, a sedentary lifestyle and being overweight all have a bearing on sperm quality and quantity. And while many men attempt to live a healthier lifestyle once they and a partner start trying for a baby, it takes the body three months to create new sperm, so to guarantee their efforts are worthwhile they should be making changes many months ahead of time.

When it occurs, infertility is as devastating for men as it is for women. What do we need to do to make sure those men get early advice and to try to reduce the number of men who have to go through this heartbreak?

I’ve long campaigned for better fertility education for both men and women. I have pushed for fertility to be added to the secondary school curriculum so that young people – men and women – understand the factors that affect their future fertility and will be in a position to make informed choices to protect it.

We know sex education works, we’ve seen levels of teenage pregnancy plummet as a result of good sex education. Now we need to apply the same principle to fertility. So we must keep challenging government and educators to also include information on fertility – female and male – in the curriculum.

We also have to remove the stigma attached to male infertility. High profile, global campaigns like Movember have done stellar work in raising awareness of prostate cancer, testicular cancer and mental health problems. Men’s fertility issues need the same attention.

We have to open up the conversation – provide information and normalise the topic as one that men can talk to each other about, devoid of embarrassment or shame. There’s still a misguided macho kudos attached to the idea of the 60-year-old new father “who’s still got it in him” – we need men to know that this is not the norm, and the risks that late fatherhood can bring. The impact of a man’s age at conception on the health of the offspring cannot be ignored.