Guys who smoke, drink, use drugs and are overweight might be facing a lot of health problems, but according to new research, their bad habits don't affect their numbers of swimming sperm. These findings contradict much of the advice given to men trying to be fathers.
In a study published this week in the journal Human Reproduction, researchers had 2,249 men from fertility clinics in the U.K. answer questionnaires about their lifestyle. The lifestyles of those who had low amounts of swimming sperm — 939 men — were compared with the other 1,310 men with higher counts.
Consumption of drugs, tobacco, alcohol and participants' body mass index did not significantly affect their counts of swimming sperm, or what's known in the scientific community as "motile sperm concentration."
"Despite lifestyle choices being important for other aspects of our health, our results suggest that many lifestyle choices probably have little influence on how many swimming sperm they ejaculate," lead author and researcher at the University of Manchester's School of Community Based Medicine, Andrew Povey, says in a statement.
What did affect sperm count in their study, was whether the men had had testicular surgery, wore something other than boxer shorts (presumably something tighter), worked in manual labour or were unemployed, or had not previously conceived. They also noted that the black men in the study had lower motile sperm concentrations, but with only 48 black men involved, that link isn't a strong one.
Povey believes that in light of these results, fertility treatment should not be put on hold as men try to build healthier habits.
"Delaying fertility treatment then for these couples so that they can make changes to their lifestyles, for which there is little evidence of effectiveness, is unlikely to improve their chances of a conception and, indeed, might be prejudicial for couples with little time left to lose," he says.
The Globe and Mail reports that the Public Health Agency of Canada and Assisted Human Reproduction Canada both consider smoking and alcohol responsible for decreasing fertility success.
"Perhaps where fertility treatment is prohibitively expensive it seems better to suggest a healthy lifestyle rather than just to advise, 'keep trying,'" University of Alberta epidemiologist Nicola Cherry tells the Globe.
So although it probably wouldn't hurt men to drop a few bad habits, those vices might not be standing in the way of having kids.
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