The spotlight’s on lifestyle issues today with the newspapers picking up on research from the Universities of Manchester and Sheffield on factors influencing sperm count. Current UK guidance from the National Institute of Clinical Excellence lists smoking, drinking alcohol, using recreational drugs and being overweight as likely to harm male fertility, but this was not supported in this study.
The Independent is one of the papers picking up on a comment by Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, who was involved in the study. “There is no need for men to become monks just because they want to be a dad,” he said, but advised that “if they are a fan of tight Y-fronts, then switching underpants to something a bit looser for a few months might be a good idea.”
The monk analogy was perhaps not the best choice. Amongst the flurry of comments on the article, there was some distracting speculation on the underwear preferences of men in Holy Orders and a wry comment from one reader that, in terms of paternal aspirations, “I would have thought that becoming a monk should have a somewhat negative impact on any such issue?” Another, looking at the accompanying photo, suggested that “If you wear green y-fronts to sunbathe, then it really doesn’t matter what your sperm count is. You’ll never get to use any of them anyway.” Quite.
So what does this research tell us?
The team set out to investigate whether common lifestyle factors are associated with low-motile sperm concentration (MSC), by recruiting 2249 men from UK fertility clinics and comparing various aspects of lifestyle in men with low MSC and men without this problem. It was not the kind of study which could establish causation. Here’s what they found:
- Low MSC was not significantly associated with with smoking and alcohol consumption, the use of recreational drugs, a high Body Mass Index or having a history of mumps or fever
- Men with a history of testicular surgery, or who were in manual work or not working, or who were of black ethnicity were more likely to have low MSC
- Men who wore boxer shorts or who had a previous conception were less likely to have low MSC
- Information about the men’s lifestyles came only from their answers to a questionnaire and at interview so there may have been inaccuracies in their recall or reporting
- Two out of five men eligible for the study chose not to take part and it is not known whether any of them did so because they had a lifestyle they did not want investigated
- The authors note that the study cannot comment on lifestyle choices that are rare and poorly reported: the finding that use of street drugs was unrelated to low MSC cannot be assumed to apply to all such drugs and all patterns of use, for example
- The men were recruited from UK fertility clinics and it is difficult to know how far the results might apply to other populations
Healthy lifestyle still important
Perhaps this will nudge other researchers to investigate these issues, but it’s too soon to ditch the lifestyle advice on the basis of this one study. As Dr Pacey commented to the BBC, “In spite of our results, it’s important that men continue to follow sensible health advice and watch their weight, stop smoking and drink alcohol within sensible limits.” The researchers also noted that, whilst this study did not find that smoking, excessive alcohol consumption and being overweight were associated with low MSC, “it remains possible that they affact fertility through some other mechanism”.
As for me, the weather’s improved at last and I’m sending out the elvish Style Police to make sure there aren’t any elves sunning themselves in green underpants.
Povey AC, Clyma J-A, McNamee R, Moore HD, Baillie H, Pacey AA, Cherry NM and Participating Centres of Chaps-uk. Modifiable and non-modifiable risk factors for poor semen quality: a case-referent study. Human Reproduction. Advance Access 12 June 2012 10.1093/humrep/des183
Fertility: assessment and treatment for people with fertility problems. NICE Clinical Guideline 11 February 2004
So, which of these does harm male fertility? The Independent 13 June 2012