In general, semen quality tended to decline as daily cell-phone use increased, research suggests.
Evidence from our latest study has demonstrated a cause-and-effect relationship between cell-phone usage and poor semen quality, recognized as a common cause for male factor infertility.
This study was the next step in our quest to define the relationship between cell phones and fertility that we first demonstrated in 2007. Our observational research showed a strong negative correlation between cell-phone usage and semen quality. In general, semen quality tended to decline as daily cell-phone use increased. Men who said they used their phones for more than four hours each day had the lowest average sperm count and motility and the lowest numbers of normal, viable sperm.
Our research over the past decade has demonstrated that oxidative stress impacts sperm health and semen quality. Reactive oxygen species (ROS) are produced continuously by spermatozoa and are neutralized by antioxidants present in the semen. A state of oxidative stress is created when ROS production exceeds the antioxidant capacity. We hypothesize that radiation emitted by cell phones in talk mode causes oxidative stress in the spermatozoa, which leads to the observed decline in semen quality.
Our recent study tested this hypothesis in a controlled, in vitro setting. Semen samples from 23 healthy donors and nine patients presenting to the infertility clinic were divided into two groups: Samples in the experimental group were exposed to radiofrequency electromagnetic waves (RF-EMW) emitted from a cell phone in talk mode for one hour. The control samples were kept under identical conditions but without RF-EMW exposure.
We then determined the level of oxidative stress by measuring the level of ROS and the total antioxidant capacity (TAC) in a combined parameter known as the ROS-TAC score, which we have demonstrated to be a more accurate measure of oxidative stress than either ROS or TAC alone.
The most remarkable finding was an increase in ROS levels in RF-EMW-exposed semen samples. This increased ROS production could be due to stimulation of the spermatozoa’s plasma membrane redox system by RF-EMW or the effect of EMW on leukocytes in the semen. We also found a decrease in sperm motility, viability, and ROS-TAC score in exposed samples.
Short-term in vitro exposure to RF-EMW should not cause a decline in sperm concentration, and our data bore out this expectation. However, chronic oxidative stress may have deleterious effects on sperm concentration. Smoking and varicocele are two common real-life examples of oxidative stress-provoking situations that we believe are worth considering in an evaluation for male factor infertility. We found no change in sperm DNA integrity in the EMW-exposed group compared with the unexposed controls. This lack of DNA damage may be explained by the brevity of exposure to cell-phone radiation or by the scavenging of free radicals by antioxidants in seminal plasma.
One of the main differences between our experimental conditions and real life is the multiple tissue layers that separate the cell phone and the reproductive organs in vivo. Further studies are needed to allow valid extrapolation of the effects seen under in vitro conditions to real-life conditions, and these are already under way in our laboratory.