London - Ciaran Hannington and his wife Jennifer had been trying for a baby for a year without success, so decided to go to their GP for help. They were expecting to be told the problem was due to Jennifer having polycystic ovary syndrome, a condition associated with abnormal hormone levels that can affect fertility.
However, just to be on the safe side, the GP said they would also carry out tests on Ciaran.
‘I remember being told there wouldn’t be any problems,’ says Ciaran, a 27-year-old trainee teacher who lives with Jennifer, a health visitor who is also 27, near Milton Keynes, Bucks.
In fact, Ciaran’s sperm count was so low he was told he was subfertile.
‘I don’t think it really sank in at that point,’ says Ciaran. ‘I just said: “Right then, OK.” It was only later that I sat down and thought about it and realised the severity of the situation. I’m not ashamed to say that I’ve cried over it. And I have wondered if I will ever be a dad. It’s difficult because there are things that can be done for Jennifer’s condition, but nothing that can be done for me.’
Since learning about his fertility problems last year, Ciaran has undergone a series of checks, including gene tests to discover why his sperm count is so low.
‘They couldn’t find a reason and have said it’s just one of those things,’ says Ciaran. ‘It does seem strange because I come from a big family - I’m from a family of four, and my mum and dad come from reasonably big families, too.
‘Like most men, when I was at university I probably drank more than I should have, and I’ve wondered if that could have had an impact.
‘I also used to do a lot of mountain biking, and I’ve read some studies suggesting that can be linked to low sperm count. But it could just be the way I’m built.’ It’s a story that is far more commonplace than many would imagine. As many as one in six couples will have difficulty conceiving - and what most people won’t realise is that in about half of such cases, the problem is due to the man.
In recent years, a number of studies have suggested the situation is getting worse, with sperm counts falling, prompting some experts to warn that male fertility is in crisis.
A major French study published a year ago found that average sperm counts fell by one-third between 1989 and 2005.
The researchers at the Institut de Veille Sanitaire in St Maurice tested samples from 26 000 men.
At the beginning of the study, the average for a 35-year-old man was 73.6 million sperm per millilitre; by 2005, it had dropped to 49.4 million per ml. Anything below 20 million is considered low.
An earlier analysis of 101 studies found that the proportion of men with a sperm count below 40 million per ml increased from 15 per cent in the Thirties to 40 per cent in the Nineties through to 2009.
The implications go beyond infertility and the psychological distress suffered by childless couples, since sperm count is considered a barometer of general health and a predictor of life expectancy.
In 2011, a Danish study found a clear link between semen quality and mortality. One theory is that sperm production depends partly on the male hormone testosterone - the hormone is thought to be protective against some diseases.
Some scientists fear that plummeting sperm counts may mean other health problems are set to rise.
As Richard Sharpe, professor of male reproductive health at Edinburgh University and one of the country’s leading experts on male fertility, puts it: ‘The present situation is not good for men.’
So what could be behind the problem? ‘We know that what happens while a baby boy is in the womb is critically important in terms of determining his future testosterone and sperm count,’ says Professor Sharpe.
A recent study from the University of Western Australia followed 2 000 men from birth, and found that those who had poor foetal growth, whose mothers smoked during pregnancy or who were overweight or underweight during childhood, were more likely to have a low sperm count.
Worryingly, around one in five women in Britain smokes in pregnancy.
But if a mother’s lifestyle during pregnancy may be partly responsible, a father’s behaviour before conception may also play a part.
Diet and lifestyle can alter the way our genes work (a process known as epigenetics), and this in turn can have knock-on effects for future generations.
A study published last year in the journal Human Reproduction showed that when male mice were fed a high-fat diet, their babies suffered fertility problems - their sperm had more DNA damage and they fathered fewer babies. (Female offspring’s fertility was also affected.)
The pattern continued in the next generation of mice.
In other words, if you eat too many fatty foods, your children - and even your grandchildren - may be more likely to be infertile.
‘Several studies have emerged in the past 18 months showing men who consume a high-fat diet are more likely to have a low sperm count,’ says Professor Sharpe.
‘But one of the most worrying developments has been that the effect is epigenetic and appears to be passed on to the next generation.
‘It raises an interesting speculation - that it’s the change in the diet of our fathers and grandfathers causing current male fertility problems.
‘We need to find out if there’s any truth in that, because if there is we really would be looking at a ticking time bomb.
‘Various factors in our modern lifestyle, diet or environment are undoubtedly making the situation worse.’
Earlier this year, a Danish study of 953 men found that those who suffered disturbed sleep had sperm counts more than a quarter lower than normal. This may be because the factors that interfere with good sleep - such as obesity, a high-fat diet, diabetes and excessive alcohol - are also linked to low sperm count.
Lack of vitamin D might also be a factor. It’s known that there’s a vitamin D receptor in the male testes, where sperm is made.
Researchers from the Medical University of Graz, in Austria, reviewed recent studies on vitamin D and maleinfertility and concluded it might be important for sperm quality and male hormone levels.
The increasing number of chemicals in our environment might be another factor, suggests Dr Simon Fishel, managing director of the CARE Fertility clinic group and a leading specialist in fertility treatment.
There’s been much focus on bisphenol A, a chemical used widely in products such as plastic food containers and tin cans. In 2010, a study of more than 500 Chinese men found that those with higher bisphenol A levels in their urine were two to four times more at risk of having low sperm concentration andquality.
The fear is that regular exposure to bisphenol A disrupts hormones, changing the way sperm is made.
‘There have been studies showing chemicals from cling film damaged fertility to the point of sterility in adolescent animals,’ says Dr Fishel. ‘So if a family is cooking a lot of food with cling film in the microwave, there’s a possibility it could cause damage.
‘There are chemicals in sweet wrappers and food packaging, and there may be oestrogenic-like compounds in the water supply from women’s use of the Pill. We live in a toxic world and young male testes are particularly sensitive. Families should be aware of how these things might impact sperm.’
However, not everyone is convinced by the bisphenol A effect: many experts argue that we are exposed to such small levels of the chemical that it could not possibly do any harm.
There’s little doubt, though, that smoking affects fertility; alcohol may do, too.
‘Some people would say “Well, I drink a lot and I have five children” - but as we know, there are genetic predispositions to certain problems,’ says Dr Fishel. ‘So what’s a toxin for one man may not be a problem for another.’ However, while lifestyle factors are implicated, the question is whether it is sperm count or sperm quality - the shape of the sperm and its ability to function - that is more important. ‘Spermatogenesis - the making of sperm - is one of the most extravagant processes in the body,’ says Sheena Lewis, professor of reproductive medicine at Queen’s University Belfast.
‘The average man produces about 500 million sperm per ejaculation - far more than heneeds.
‘So even if you had a 50 per cent drop, it wouldn’t make a man infertile. The number of sperm is not the important factor: it’s quality, not quantity, that really counts.’
Her work has been focused on the DNA - the genetic blueprint - of sperm, which is crucial to it working at its best.
‘If you have 500 million sperm per ejaculation, but each one has DNA damage, then it’s highly unlikely it will make a baby,’ says Professor Lewis.
Dr Fishel agrees it’s not just about sperm count. ‘We know there are men with sperm count levels so low that if they pitched up at a fertility clinic they’d be told they were subfertile - and yet they have children.
‘But I think the sperm count story is a signal something is going wrong, and it’s probably related to lifestyle and environment.’
And yet the problem might be far simpler, according to Dr Allan Pacey, senior lecturer in andrology at the University ofSheffield.
Dr Pacey believes that the discussions about sperm counts, cling film and waistlines are just a distraction from a far bigger and more scientifically credible problem: men are leaving it too late before they try for fatherhood.
‘There’s a lot of bad evidence out there making scary claims,’ he says. ‘Most of the studies on male fertility are animal studies or done in fertility clinics, meaning the participants will already be known to be having difficulty conceiving.
‘It’s difficult to get an unbiased view of the general population.’ Furthermore, a study he carried out last year found little evidence for many mooted causes of infertility. His team compared the lifestyles of 939 men with poor sperm quality with 1,310 men with normal sperm quality.
‘There was no effect from body mass index, smoking, alcohol or recreational drugs,’ he says.
‘The only thing we found to be a risk was tight boxer shorts.’ (Tight underpants raise the temperature of the testes, which negatively affects sperm production.)
‘Sperm counts aren’t falling, but fertility rates are - and that’s largely because people are waiting until they’re older to have children,’ says Dr Pacey.
‘Twenty or 30 years ago, if you were an infertile man trying for a baby, you would probably be in your early 20s and so it might take you a bit longer, but you’d get there in the end. Now, you might be 35 or 40 before you start trying, and you’ll have more of a problem getting your partner pregnant because your age just compounds the problem.
‘We’ll never be able to increase sperm count, and so the message is simple: try for a baby early.’
That will be of little comfort to couples such as Paul and Liz Lockwood. They married six years ago, when they were aged 26 and 25 respectively, and decided to try for a baby straight away because Liz, like Ciaran’s wife, has polycystic ovary syndrome.
After 18 months without success, they sought medical help — only to learn that Paul has a low sperm count (10-12 million per ml), probably as a result of an operation he’d had for an undescended testicle at the age of 11.
‘I was shocked,’ says Paul, an insurance adviser who lives with Liz, a freelance editor, in South Wales. ‘I don’t think any man expects this. And I felt less of a man, I suppose, because I couldn’t give Liz a child.’
Sadly, after two unsuccessful rounds of ICSI - where sperm is injected directly into the egg - the couple are still without the baby they long for.
After an extremely stressful few years, they are taking a few months before deciding what to do next.
‘Neither of us ever dreamed the cause of the problem would be me,’ says Paul. ‘The doctors are surprised we’ve not been able to conceive yet - we’re young and have time on our hands, so we’re hopeful that we will get there.’