A new study by the University of Exeter strongly suggests that keeping a smartphone in a trouser pocket can have a detrimental effect on male fertility.
At the moment, about 14% of couples living in high and middle-income countries have difficulty conceiving, and unexplained declines in semen quality have been reported in several countries.
Mobile phones emit electromagnetic radiation (EMR), a low-level radio frequency of between 800 to 2200 MHz which can be absorbed by the human body.
While this level of radiation is considered safe for humans, several studies have found that the electromagnetic fields emitted from mobile phones can result in more headaches and affect resting blood pressure.
Radiation and sperm count
Led by Dr Fiona Mathews from the Biosciences department, a team of researchers analysed 1,492 samples from 10 studies, which featured participants from fertility clinics and research centres.
Sperm quality was measured in three different ways – motility, i.e. the ability of the sperm to move properly towards an egg; viability, which refers to the proportion of sperm that were alive; and concentration, i.e. the number of sperm per unit of semen.
In the control groups, 50% - 85% of the sperm were found to have normal movement, but when looking at the sperm count of individuals exposed to mobile phones, sperm motility decreased by 8.1%, while viability decreased by 9.1%. The effects on sperm concentration were not clear.
The results were consistent across in-vitro studies conducted under controlled conditions and observational in-vivo studies conducted on men in the general population.
More studies needed
While the study found a strong link between radiation emitted by mobile phones and male fertility, more research still needs to be done to rule out other environmental factors not explored by the researchers, such as exposure to smoking and exposure to Wi-Fi signals from laptops.
"This study strongly suggests that being exposed to radio-frequency electromagnetic radiation from carrying mobiles in trouser pockets negatively affects sperm quality," said Mathews.
"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."
The results of the study, entitled: "Effect of mobile telephones on sperm quality: A systematic review and meta-analysis" are published in the journal Environment International.