“Working on a laptop wirelessly may hamper a man’s chances of fatherhood,” the Daily Mail has today reported. Its story is based on a laboratory study that found that healthy sperm placed under a laptop connected to the wireless internet for four hours, showed less movement and more changes to their genetic code than ‘control’ sperm not near a wi-fi connected laptop.
Men should not be too concerned by the findings from this preliminary laboratory study, as they are not proof that using a wireless laptop on the lap reduces male fertility. It is simply not possible to draw conclusions about the possible effect of wi-fi on male fertility from a laboratory study that involved sperm taken from only 29 donors.
As one expert pointed out, sperm in the laboratory are outside the human body and do not have the protection of the tissues and fluids of the testes in which they are stored. Therefore they might be more vulnerable to damage.
It is also not clear whether the effects seen would be sufficient to affect fertility. Further studies are needed before it is known what effect, if any, exposure to wi-fi has on sperm in the body or on male fertility.
The study was carried out by researchers from Nascentis Reproductive Medicine in Argentina and the Eastern Virginia Medical School in the US. The study was published in the peer-reviewed journal Fertility and Sterility. No external funding sources were reported.
In its report, the BBC appropriately pointed out that this was preliminary research and further studies are needed. The story also carried a lengthy critical assessment from an independent expert pointing out why the research may not reflect what happens in a real-life setting.
The_ Daily Mail_ explained how the study was conducted and includes comments on its limitations from an expert. Its headline that ‘Radiation from wi-fi connections can reduce sperm activity in up to a quarter of men’ may suggest that the study was carried out in humans, which is not the case.
This was an experimental laboratory study looking at how sperm samples were affected by exposure to a nearby laptop wirelessly connected to the internet. The sperm samples were donated prior to exposure to wi-fi, meaning the study looked at particular sperm isolated from their normal environment.
Studies that look at components of an organism outside of their biological context are called ‘in vitro’ studies, which literally means studies ‘within glass’ due to their use of apparatus such as test tubes and Petri dishes. They differ from ‘in vivo’ studies, which look at what occurs in a living organism such as a person.
The researchers point out that people using wi-fi may be exposed to radio signals by absorbing some of the transmitted energy in their bodies. They say that portable laptops, positioned in the lap, may expose the genital area to radio-frequency magnetic waves (RF-EMW) as well as high temperatures. They mention the suggestion that male fertility has declined in recent decades, and that this may be attributed to exposure to environmental factors such as RF-EMW.
This type of study is an appropriate first step to look at whether wi-fi laptops might damage sperm, but cannot fully represent what would happen in real life. Further studies in humans would be needed to determine whether use of wi-fi laptops can affect fertility.
The researchers collected 29 semen samples from healthy donors aged between 26 and 45. They measured each sample’s number of sperm, the sperm’s ability to swim (motility) and its shape (morphology), all of which demonstrate the quality of the sperm. Using special techniques they isolated the healthiest moving sperm for the study.
Each of the 29 samples was centrifuged to form a ‘sperm pellet’ and then divided into two Petri dishes. One dish was stored for four hours at room temperature under a laptop computer connected to the internet by wi-fi. The laptop was set to constantly transmit and receive data via wi-fi. The distance between the samples and the laptop was 3cm, which researchers estimated as the distance between a computer resting on the lap and the testes.
The other dish was stored under similar conditions and also at room temperature, but in a separate room away from any computers or other electronic devices. Both sets of sperm samples had their temperature recorded every five minutes.
After four hours, researchers measured all the samples for sperm vitality and motility. They also looked at whether the sperm’s DNA (its genetic code) had been damaged, by looking at the level of breakage in the DNA.
At the start of their study, most of the sperm samples were normal, although samples from three men were low in semen volume and three contained abnormally shaped sperm.
When they compared the sperm exposed to wi-fi from a laptop to those not exposed, they found that:
The researchers conclude that laptop computers connected wirelessly to the internet reduced the quality of sperm and induced DNA damage in the laboratory. They say the findings suggest that prolonged use of portable computers on the lap may reduce male fertility and this warrants further investigation.
This small laboratory study found that the movement and DNA of sperm outside of the human body may be affected by close exposure to a laptop connected to the internet by wi-fi.
While the findings of this lab-based study suggest that the effects of wi-fi on sperm may be worth investigating further, its findings should be interpreted in context:
Studies following men in the general population would be needed to investigate whether wi-fi connected laptops have any effect on male fertility.