New research has signaled that smartphones may impact the sperm quality of young men. Fear not, though. While researchers in the field have praised the robustness of the study, they have added that the findings shouldn’t spark panic and the cause of humanity’s “spermageddon” remains elusive. 

It’s been widely suggested that sperm count and quality has slumped in the past 50 years. One particular study found that the demise was most notable after 2005 when sperm counts from healthy young men in the US nosedived. This new research asks the question: could smartphones be to blame?

Scientists at the University of Geneva looked at data on 2,886 Swiss men aged 18 to 22, recruited between 2005 and 2018 at six military conscription centers nationwide. 

“Men completed a detailed questionnaire related to their lifestyle habits, their general health status and more specifically the frequency at which they used their phones, as well as where they placed it when not in use,’’ Serge Nef, co-director of the study and professor in the Department of Genetic Medicine and Development at the UNIGE Faculty of Medicine and at the SCAHT – Swiss Centre for Applied Human Toxicology, said in a statement. 

The findings showed that sperm concentration was significantly higher in the group of men who did not use their phone more than once a week (56.5 million per milliliter) compared with men who used their phone more than 20 times a day (44.5 million per milliliter) – that’s a 21 percent decrease.

The data also implies that sperm quality dropped more sharply during the first study period in 2005-2007 than in later periods in 2008-2011 and 2012-2018.

“This trend corresponds to the transition from 2G to 3G, and then from 3G to 4G, that has led to a reduction in the transmitting power of phones,’’ explains Martin Röösli, study author and associate professor at the Swiss Tropical and Public Health Institute. 

The idea is that electromagnetic radiation is, somehow, impacting sperm quality. Many people keep their smartphone in their trouser pocket, very close to the groin, potentially making this sensitive part of the body susceptible to the electromagnetic waves beaming out of the device.

However, this link is by no means conclusive. Lead study author Rita Rahban notes: “The number of people in this cohort indicating that they did not carry their phone close to their body was too small to draw a really robust conclusion on this specific point.”

It’s also possible that the apparent drop in sperm fitness is associated with any number of technological, social, or environmental changes that have arisen in recent decades. For instance, a seminal book (no pun intended) by Professor Shanna Swan called Count Down argued that the “sperm apocalypse” is being driven by environmental pollutants used in manufacturing everyday products, such as phthalates from plastic and per- and poly-fluoroalkyl substances (PFAS) used, for example, in waterproofing.

Independent scientists commenting on the new research remarked that it was a “very well-conducted” study that provides an interesting piece of the puzzle. However, people should be cautious when interpreting the results as they only show an association between mobile phone use and semen quality, not a causal link. 

“We cannot be sure that the mobile phone is not a surrogate marker for another aspect of the men’s lifestyle or occupation that is the real cause of any changes to their sperm quality,” said Allan Pacey, Professor of Andrology at the University of Manchester, commenting on the new study.

“I am not sure it really changes the advice I would give to men who are concerned about their fertility. If men are concerned, then keeping their phones in a bag and limiting their use is a relatively easy thing for them to do. But there is currently no evidence that will improve their sperm quality (that would need a randomised controlled trial),” Professor Pacey noted. 

He concluded: “As for me, I will be continuing to keep my phone in my trouser pocket.”

The study is published in the journal Fertility & Sterility.