Men are bombarded with messages that smoking and alcohol consumption can decrease their chances of having a child.
But, according to a leading fertility expert, the ‘single biggest risk factor’ is down to a clothing choice; namely their underwear.
Allan Pacey, who is a professor at the University of Sheffield, told an audience at Cheltenham Science Festival that men who were tight pants are far more likely to have poor sperm.
‘We did a study of 2,500 young men and we thought we needed to be worried about smoking and alcohol consumption,’ he said.
'The single biggest risk factor we found was wearing tight underwear.
‘Men who wear tight underwear are two and a half more times likely to have poor sperm than men who wear boxer shorts.’
Prof Pacey also said children born to men over 40 are more likely to suffer from conditions like schizophrenia, autism, Down’s syndrome and dwarfism.
He explained that men produced sperm throughout their life but as they got older the quality declined.
‘You should be going for the hot, virile toy boys, popstars and boybands – that is where you should be heading,’he added.
‘Men above the age of 40 are much less fertile than men under the age of 24, and arguably less successful than their partners at this age.
‘That isn’t because there has been a dramatic change in the number of sperm produced, it is just by the time you are aged 40 or 45 the quality has declined.
‘Charlie Chaplin was 72 when he had his 11th child with his fourth wife. He was quite an exception and when we pat older guys on the back for having done the deed, I think we are probably sending out the wrong message.'
He continued: ‘The health of children with older fathers is much poorer than the health of children with younger fathers.
‘A man’s contribution to the risk of miscarriage kicks in once he gets to 40. It is a little known fact that problems with sperm can independently contribute to his partner’s risk of miscarriage.’
Source: Metro