New research shows men who keep a mobile phone in their trouser pocket could be inadvertently damaging their chances of becoming a father. However, independent experts question the clinical significance of the impacts found in the study.
Researchers from the University of Exeter conducted a systematic review of the findings from ten studies, including 1,492 samples, with the aim of clarifying the potential role of this environmental exposure. The research was published this week in the journal Environmental International.
Participants in the studies were from fertility clinics and research centres, and sperm quality was measured in three different ways: motility (the ability of sperm to move properly towards an egg), viability (the proportion of sperm that were alive) and concentration (the number of sperm per unit of semen).
In control groups, 50-85% of sperm have normal movement. The researchers found this proportion fell by an average of 8 percentage points when there was exposure to mobile phones. Similar effects were seen for sperm viability. The effects on sperm concentration were less clear.
“Given the enormous scale of mobile phone use around the world, the potential role of this environmental exposure needs to be clarified.” said lead researcher Dr Fiona Matthews in a media release. This study strongly suggests that being exposed to radio-frequency electromagnetic radiation from carrying mobiles in trouser pockets negatively affects sperm quality. This could be particularly important for men already on the borderline of infertility, and further research is required to determine the full clinical implications for the general population.”
Our colleagues at the UK SMC collected the following expert commentary. Feel free to use these quotes in your reporting. If you would like to contact a New Zealand expert, please contact the SMC (04 499 5476; firstname.lastname@example.org).
Prof Sheena Lewis, Professor of Reproductive Medicine at the Centre for Public Health, Queen’s University Belfast, said:
“The outcomes of the study are based on large numbers of men but caution must be exercised in interpreting the results as there are many differences between the different study designs – some are in vivo, some are in vitro, some are infertile men, some are from the general population – and the decrease in 8% motility may not be of significance in terms of the man’s overall fertility potential.”
Prof Neil McClure, Professor of Obstetrics and Gynaecology at Queen’s University Belfast, said:
“This paper has taken a number of much smaller papers and grouped them together. However, the quality of data that has been pooled is flawed.
“Subjects are often those who are already attending an infertility clinic and subjects have self-reported their use of mobile phones: it is not clear if this is continuous or intermittent usage. It would be difficult to see how holding a mobile phone to one’s ear could have a significant pathological effect on sperm quality.
“What is clear is that a proper, randomised study of adequate scale is necessary if this question is to be answered. This study, and to be fair by its own admission, does not achieve that goal.”
Dr Allan Pacey, Senior Lecturer in Andrology at the University of Sheffield, said:
“There have been some crazy and alarming headlines on this subject. But, in my opinion, the studies undertaken to date have been somewhat limited. That’s because they have either sperm kept in a dish irradiated at frequencies used by mobile phones (which is not realistic) or they have made assessments of men’s phone habits without adequately considering other aspects of their lifestyle.
“Therefore, whilst undertaking a meta-analysis can be a good idea, in this instance I don’t think it helps us decide whether there is any risk of keeping a phone in your trouser pocket or not. What we need are some properly designed epidemiological studies where mobile phone use is considered alongside other lifestyle habits. Until that time, I will be continuing to keep my iphone in my trouser pocket!”