Cell phones and low sperm quality, there is a correlation: study explains which

It doesn’t matter whether you keep your smartphone in your trouser pocket or not, and 4G seems to have less impact

Frequent use of cell phones appears to be associated with lower sperm concentration and total sperm count. And it doesn’t matter whether you keep your smartphone in your trouser pocket or not. This is what emerges from a large cross-sectional study conducted by researchers from the University of Geneva in collaboration with the Swiss Tropical and Public Health Institute. Much research has highlighted a decline in sperm quality over the last 50 years, highlight the authors of the work published in ‘Fertility & Sterility’. Various environmental and lifestyle factors have been proposed to explain the phenomenon, but whether electromagnetic radiation emitted by mobile phones plays a role has yet to be demonstrated, they note.

For this reason it was decided to investigate this aspect. After conducting the first national study in 2019 on the sperm quality of young men in Switzerland, the team worked on new study based on data from 2,886 Swiss aged between 18 and 22, recruited between 2005 and 2018 in six military conscription centers. Under the lens the association between the participants’ sperm parameters and their use of mobile phones. With a questionnaire, the experts collected information “on their lifestyle habits, general state of health and more specifically the frequency with which they used their cell phones, as well as where they placed them when they were not using them”, explains the expert who co-directed the study, Serge Nef, full professor of the Department of Genetic Medicine and Development, Faculty of Medicine of Unige and Scath (Swiss Center for Applied Human Toxicology).

These data revealed an association between frequent cell phone use and lower sperm concentration. While they did not detect a link with low sperm motility and morphology. The average sperm concentration was significantly higher in the group of men who did not use the phone more than once a week (56.5 million/ml) compared to those who used it more than 20 times a day (44.5 million/ ml). This difference corresponds to a 21% decrease in sperm concentration for frequent users. To explain what impact this aspect has, it should be remembered that according to the values ​​established by the World Health Organization (WHO), a man will most likely take more than a year to conceive a child if his sperm concentration is less than 15 million per milliliter. Furthermore, the percentage chance of pregnancy will decrease if the sperm concentration is less than 40 million per milliliter.

What is the situation today?

It is generally estimated that the number of sperm has dropped from an average of 99 million per milliliter to 47 million per ml. And it is believed that this phenomenon is the result of a combination of environmental factors (endocrine disruptors, pesticides, radiation) and lifestyle habits (diet, alcohol, stress, smoking). Now the new study turns the spotlight on a possible further factor to focus on: the use of smartphones. This inverse association, greater use of cell phones-lower sperm concentration, the authors point out, was more pronounced in the first study period (2005-2007) and gradually decreased over time (2008-2011 and 2012-2018). “The trend corresponds to the transition from 2G to 3G and then from 3G to 4G, which led to a reduction in the transmission power of telephones”, explains Martin Röösli, Swiss Tph institute.

The data analysis also appears to show that the location of the phone, for example stored in the trouser pocket, is not associated with lower semen parameters. “However, the number of people in this group who indicated not carrying their phone close to their body was too small to draw a really solid conclusion on this specific point,” adds Rita Rahban, Unige and Scath, first author and co-leader of the study. Experts highlight a limitation of the study linked to the fact that it is based on self-reported data. To overcome this limitation, a study funded by the Federal Office for the Environment was launched in 2023 which aims to directly and precisely measure exposure to electromagnetic waves, as well as the types of use of mobile phones: calls, web browsing, messages and evaluate their impact on male reproductive health and fertility potential.

The data will be collected via an app that each future participant will download onto their mobile phone. The research team is actively recruiting participants. Because, observes Rahban, much “remains to be discovered: do the microwaves emitted by cell phones have a direct or indirect effect? ​​Do they cause a significant increase in temperature in the testicles? Do they influence the hormonal regulation of sperm production?”, are some of the questions to be explored further.