Does electromagnetic radiation emitted by mobile phones affect semen quality? While various environmental and lifestyle aspects have been proposed to clarify the decline in semen quality observed over the past fifty years, the role of mobile phones has yet to be demonstrated. A team from the University of Geneva (UNIGE), in collaboration with the Swiss Tropical and Public Health Institute (Swiss TPH), has published a significant cross-sectional study on the topic. It shows that frequent use of mobile phones is related to a lower sperm concentration and total sperm count. Nevertheless, researchers didn’t find any association between cell phone use and low sperm motility and morphology. Read the leads to Fertility & Sterility.

Semen quality is decided by the assessment of parameters resembling sperm concentration, total sperm count, sperm motility and sperm morphology. In accordance with the values established by the World Health Organization (WHO), a person will most likely take multiple 12 months to conceive a baby if his sperm concentration is below 15 million per milliliter. As well as, the proportion likelihood of pregnancy will decrease if the sperm concentration is below 40 million per milliliter.

Many studies have shown that semen quality has decreased over the past fifty years. Sperm count is reported to have dropped from a mean of 99 million sperm per milliliter to 47 million per milliliter. This phenomenon is regarded as the results of a mixture of environmental aspects (endocrine disruptors, pesticides, radiation) and lifestyle habits (food regimen, alcohol, stress, smoking).

Assessing the impact of mobile phones

Is the cell phone also in charge? After conducting the primary national study (2019) on the semen quality of young men in Switzerland, a team from the University of Geneva (UNIGE) has published the most important cross-sectional study on this topic. It relies on data from 2886 Swiss men aged 18 to 22, recruited between 2005 and 2018 at six military conscription centres.

In collaboration with the Swiss Tropical and Public Health Institute (Swiss TPH), scientists studied the association between semen parameters of 2886 men and their use of mobile phones. ”Men accomplished an in depth questionnaire related to their lifestyle habits, their general health status and more specifically the frequency at which they used their phones, in addition to where they placed it when not in use,” explains Serge Nef, full professor within the Department of Genetic Medicine and Development on the UNIGE Faculty of Medicine and on the SCAHT – Swiss Centre for Applied Human Toxicology, who co-directed the study.

These data revealed an association between frequent use and lower sperm concentration. The median sperm concentration was significantly higher within the group of men who didn’t use their phone greater than once per week (56.5 million/mL) compared with men who used their phone greater than 20 times a day (44.5 million/mL). This difference corresponds to a 21% decrease in sperm concentration for frequent users (>20 times/day) in comparison with rare users (<1 time>

Is 4G less harmful than 2G?

This inverse association was found to be more pronounced in the primary study period (2005-2007) and steadily decreased with time (2008-2011 and 2012-2018). ”This trend corresponds to the transition from 2G to 3G, after which from 3G to 4G, that has led to a discount within the transmitting power of phones,” explains Martin RÖÖsli, associate professor at Swiss TPH.

Previous studies evaluating the connection between the usage of mobile phones and semen quality were performed on a comparatively small number of people, rarely considering lifestyle information, and have been subject to selection bias, as they were recruited in fertility clinics. This has led to inconclusive results.”

Rita Rahban, senior researcher and teaching assistant within the Department of Genetic Medicine and Development within the Faculty of Medicine on the UNIGE and on the SCAHT, first writer and co-leader of the study

It doesn’t matter where you set your phone

Data evaluation also seems to indicate that the position of the phone – for instance, in a trouser pocket – was not related to lower semen parameters. ”Nevertheless, the number of individuals on this cohort indicating that they didn’t carry their phone near their body was too small to attract a extremely robust conclusion on this specific point,” adds Rita Rahban.

This study, like most epidemiologic studies investigating the consequences of cell phone use on semen quality, relied on self-reported data, which is a limitation. By doing so, the frequency of use reported by the person was assumed to be an accurate estimate of exposure to electromagnetic radiation. To deal with this limitation, a study funded by the Federal Office for the Environment (FOEN) was launched in 2023. Its aim is to directly and accurately measure exposure to electromagnetic waves, in addition to the forms of use – calls, web navigation, sending messages – and to evaluate their impact on male reproductive health and fertility potential. The information might be collected using an application that every future participant will download to their cell phone. The research team is actively recruiting participants for this study.

The aim can also be to raised describe the mechanism of motion behind these observations. ”Do the microwaves emitted by mobile phones have a direct or indirect effect? Do they cause a big increase in temperature within the testes? Do they affect the hormonal regulation of sperm production? This all stays to be discovered,” concludes Rita Rahban.