Over dinner one evening six years ago, Craig Franklin gave his wife Katie permission to leave him.
'He looked me in the eye and said, "I'm not good enough. I can't give you what you want. Go and find someone who can",' recalls Katie who, through tears, rebuffed her husband's suggestion, but admits: 'I couldn't cope with how he was behaving. A few times, I wanted to run away.'
Weeks earlier, Craig had been told he was infertile, a revelation that not only almost destroyed the couple's marriage but would cost Craig his job and cause a financially crippling compulsive spending habit.
Although he and Katie have since rebuilt their relationship, he is still coming to terms with the fact they can't have children.
'It feels emasculating,' says Craig, 42. 'I also feel grief, that I've had that choice ripped away.'
He is far from alone in suffering the devastating effects of male infertility. One in ten men in the UK are similarly impacted and those figures look set to increase, with research revealing that sperm counts among Western males have more than halved in the past 40 years.
Craig Franklin, 42, from Clacton-on-Sea, Essex, gave his wife Katie, 41, (both pictured) permission to leave him, just weeks after he had been told that he was infertile
Although everything from excess alcohol consumption to the way the male foetus develops in the womb is being considered as a factor, scientists are still not really sure why.
When a couple are struggling to conceive, we tend to assume the woman has problems. In fact, men account for 50 per cent of all difficulties.
Yet, while there are 8,000 gynaecologists and obstetricians focusing on the female reproductive system in the UK, there are fewer than 200 andrologists — specialists who deal with male fertility.
In new BBC documentary Stand Up To Infertility comedian Rhod Gilbert, 52, whose poor sperm motility means he is struggling to have children with wife Sian, looks at why so many men are struggling to become fathers — and why so few talk about it.
'Men are certainly marginalised,' says Professor Sheryl Homa, an andrologist and director of male fertility clinic Andrology Solutions in London.
'Society focuses on female fertility issues. It's always the woman being asked, "When are you going to have children?" In terms of how doctors are trained, there is a huge emphasis on gynaecology but negligible teaching when it comes to the male reproductive system.'
Equally significant, however, is the stigma that surrounds male infertility.
'Men consider their fertility as equivalent to their virility, and I don't think that is so true for women,' she adds. 'Being unable to father a child has a huge psychological impact on men, both for themselves and where they view their status in society.'
The revelation cost Craig (pictured) his job, he developed a financially crippling compulsive spending habit, and he is still coming to terms with the fact they can't have children
To know they are 'at fault' can be doubly distressing. She says: 'It's very difficult for men to articulate this. It becomes internalised and puts a lot of stress on their relationship.'
Craig and Katie, 41, started trying for a baby after their 2010 wedding. When they failed to conceive, both assumed the issue was Katie's.
'As a man, you don't tend to think it's a problem on your side,' says Craig, from Clacton-on-Sea, Essex.
In 2013, Katie's GP referred her to a gynaecologist for tests. It was only when they came back clear that Craig visited his GP, who took a sample for semen analysis.
When called back, the couple were shocked by the GP's bluntness. 'He said you have no sperm. You can't have children,' Craig says.
Katie, who burst into tears in the surgery car park afterwards, adds: 'I felt it was as if, "You're a man, you just have to deal with it".'
Katie, a hospital theatre assistant, insisted on a second opinion. Craig was referred to a hormone specialist at Colchester Hospital who, after blood tests, diagnosed Craig with non-obstructive azoospermia, which means his body is unable to produce sperm. In Craig's case it was genetic and caused by low testosterone.
I felt that I wasn't a proper man
He was prescribed testosterone injections every three months but told his chances of fathering a child were slim.
His powerlessness quickly gave rise to anger, his once laid-back personality barely recognisable as he began hitting walls and doors.
'He would shout at me,' says Katie, who didn't feel personally threatened but says: 'It got to the point where I knew he'd have to walk away from an argument. That's the only way he'd calm down. We learned together to deal with it.'
'I became very closed. I didn't want to talk to friends,' says Craig. 'I wasn't the person Katie married. I considered counselling but couldn't find any experts geared up to deal with my specific situation.'
Several weeks after his diagnosis, Craig suggested she leave him. 'I said, "If you want to find someone else who can give you a child naturally, then go, I understand",' he recalls. 'She said if she did, the vows she took on our wedding day would mean nothing.' Katie adds: 'We ended up crying together.'
As a coping mechanism, Craig became a compulsive spender, buying endless gadgets for his car and computer he didn't need.
'I'd get the parcels delivered to work, but Katie eventually caught on and started asking questions,' says Craig. 'I started hiding it more.'
A year after his diagnosis, Katie found a credit card statement that showed he'd run up bills of £20,000.
Anthony Shapley, 33, (pictured) a digital marketer from Exeter, Devon, suffered from Hodgkin lymphoma, a cancer of the lymphatic system, as a child, which has affected his fertility
'I was livid,' says Katie, who took control of all his bank cards and gave him an ultimatum: "I said, 'Stop doing what you're doing, or I won't be here any more".'
Craig stopped, but lost his job as an IT helpdesk worker in 2017 because he 'didn't have the drive to do anything'. Shortly afterwards, he got another job and is now an IT support analyst.
In 2019, the couple paid £8,000 for IVF, a procedure they weren't eligible for under their local NHS at the time. An embryo formed but failed. 'Although it was only a cluster of cells it felt as if our child had died,' says Craig.
They are now considering embryo donation to give fertility treatment the best chance of success.
'Katie is aware that as she gets older her fertility is an issue,' says Craig.
'I am still desperate to have children. It does hurt. But I don't blame Craig at all,' says Katie.
Antidepressants, which increasing numbers of men take in these troubled times, have been found to affect sperm motility.
Research by scientists in Germany last month found men who have had coronavirus may also have a lower sperm count. But this could simply be a temporary effect, says Professor Homa. An unhealthy diet, stress and excess alcohol have also been linked to lower sperm counts.
'It's absolutely true that lifestyle exacerbates the situation but, invariably, if you are infertile there is an underlying clinical cause,' says Professor Homa.
Underlying infections can also factor, along with hormone imbalance and illnesses such as diabetes.
'A lot of doctors say there's not a lot you can do about male infertility. It's not true,' says Professor Homa. 'You can treat infections with antibiotics, treat diabetes and sometimes alter hormone levels.'
Chemotherapy can also affect male fertility, by stopping sperm production.
Anthony Shapley, 33, a digital marketer from Exeter, Devon, suffered from Hodgkin lymphoma, a cancer of the lymphatic system, as a child.
In remission since age five, he was warned at 18 by his consultant that his fertility may have been affected by the chemotherapy he had.
'I was shocked,' says Anthony. Yet it was only at the age of 21, after meeting his girlfriend, that the ramifications sunk in.
'We wanted to try for children,' says Anthony. In his mid-20s, semen analysis revealed no sperm. 'I was gutted,' he says. 'I wanted the joy of watching someone grow up.'
He and his girlfriend were referred to a fertility clinic, where he was scheduled to have a testicular biopsy to see if his sperm was blocked.
Adam Haslam, 38, and his wife Emma, 40, (both pictured) had been trying for a baby for a year when it was revealed Emma was perimenopausal and Adam had a low sperm count
If sperm is found in the testes, it can be harvested and used for intracytoplasmic sperm injection, where individual sperm are injected into an egg to increase the chances of fertilisation.
But in 2016, 12 months after being provisionally booked in, he had yet to be offered an appointment.
'I felt angry,' he says. 'My partner was understanding but it made our relationship challenging. It should be easier for people like me to get answers.'
Since they broke up in 2017 Anthony has told prospective girlfriends about his infertility before their first date.
'I think it's better to be upfront,' he says. 'Some don't bat an eyelid. Others politely say they want a family. Sometimes they'll stop talking to me.' He finds it difficult to discuss with friends. 'It makes me upset,' he says.
Adam Haslam, 38, and his wife Emma, 40, had been trying for a baby for a year when they visited their GP in 2013. Their tests revealed that Emma was perimenopausal and Adam had a low sperm count.
When the couple, from Cononley, North Yorkshire, told his mother about their fertility struggles, she revealed Adam had had a procedure to correct an undescended testicle as a child.
A couple of years later, after they had still failed to conceive, they asked doctors if the procedure Adam had as a child could be looked at as a cause. 'They said there were no further tests. There was no support,' says Adam.
Emma says: 'I found it easy to talk to my friends. Adam didn't. He said there was no point. He'd always been jovial but became quiet.' Adam admits, 'I became embarrassed, which turned me into a bit of a recluse.'
They were unable to afford the cost of IVF in the UK, where one cycle can cost £10,000, and they were not eligible on the NHS because Emma, having already lost 6 st, was still 2 st over the maximum weight limit in her area.
So the couple had the procedure in the Czech Republic, where IVF is around 40 per cent cheaper, including flights and accommodation. They used donated sperm and egg and their son was born in August 2019.
They set up yourivfabroad.co.uk, a business advising how to navigate IVF abroad.
Reverend Matt Woodcock, 45, discovered he had a low sperm count 18 months after he and wife Anna, 43, a council administrator, started trying for a baby in 2005.
His GP took a sperm sample that revealed he had 'virtually' no sperm. 'My doctor said, "If I was a betting man I'd bet you couldn't have children"... He was unbelievably rude,' says Matt, from York.
Matt Woodcock, 45, from York, discovered he had a low sperm count when he and wife Anna, 43, (both pictured) were trying for a baby, but said his doctor was 'unbelievably rude' about it
Desperate for a second opinion, the couple sought a private consultation with a urologist. He found that whereas the average man produces between 40 million and 300 million sperm per millilitre of semen, Matt's sample had just 37 sperm per millilitre.
'We both cried out eyes out,' says Matt. 'Anna had a massive maternal instinct and I felt horrible I couldn't give her what she wanted. Anna said we were in this together. But I felt that I wasn't a proper man, that my wife wouldn't find me attractive any more and was going to leave me.
'I made a joke of it with male friends. I told them I was firing blanks. I didn't know how else to handle it. Most recognised it could happen to anyone.'
Not everyone was as sensitive, however: 'Some would say, "I only have to look at my wife and she gets pregnant". I laughed it off but was silently seething.'
In 2008, after trying for three years, the couple, who were told there was no funding available in their area for IVF on the NHS, used their savings to pay for it. \
After it failed, a family friend funded two further attempts. The third attempt resulted in twin girls, Heidi and Esther, who were born in December 2010.
'We were both wailing when we saw two flashing heartbeats on the monitor. We've been so blessed,' says Matt, who has written a book, Becoming Reverend, about his fertility struggles.
'The problem with men is they internalise everything. But I realised if it had happened to me it must be happening to millions of others too and they shouldn't suffer in silence.'
Rhod Gilbert: Stand Up To Infertility is available now on BBC iPlayer. For more information on male infertility and support available, visit himfertility.com.