Study summary and analysis written by Ann E. Laubscher, M.A.
This post is a summary and analysis of an independent scientific study titled "Effect of mobile telephones on sperm quality: A systematic review and meta-analysis".
Cell phones emit radio-frequency electromagnetic radiation (RF-EMF). That means that there is a low level of electromagnetic radiation that the International Commission on Non-Ionizing Radiation Protection (ICNIRP) deems acceptable for body tissue to absorb during exposure. Most cell phones emit close to 1.4 watts/kilogram, well under the 2.0 W/kg limit set by ICNIRP.
However, that limit does not stipulate that there will be no effects to the tissues or exposed body parts. This is disconcerting when considered in conjunction with the difficulties in conception faced by 14% of couples, 40% of whose cases stem from male fertility issues. Men frequently carry cell phones on belt clips or in pockets close to their genitalia, giving rise to the question of whether the RF-EMF exposure is one of the environmental factors contributing to male infertility problems.
This meta-analysis, or review and analysis of previously conducted research, examines the results of 10 different RF-EMF exposure studies on three qualities that relate to sperm fertilization capacity: motility, viability, and concentration. Not all studies presented results for each quality, so the statistical analyses on each quality had its own pooled subject size. All studies adhered to the World Health Organization's collection and analysis standards. One typical problem with meta-analytic studies, heterogeneity, or the expected variation due to chance, was also an issue that was appropriately addressed by conducting both fixed effects model (FEM) and random effects model (REM) analyses.
Motility is the ability of sperm to move effectively. Nine of the ten studies examined the effects of RF-EMF on sperm movement. Of those nine, six independently reported results that indicate RF-EMF has a negative effect on motility. When all nine were statistically examined together (1448 samples), both FEM and REM analyses suggested that RF-EMF exposure had a negative effect on motility. This was true of both in vivo (within body) and in vitro (out of body) exposure samples of sperm. The samples that were exposed to cell phones for longer periods showed less motility than those exposed for shorter periods.
Viability is a measure that examines whether non-motile, or non-moving, sperm are alive or dead. Five of the studies contained viability results (816 samples) included in the meta-analysis. Four of those five studies independently reported that cell phone exposure was linked to lower sperm viability. When statistical analyses were performed on all five studies, the negative association was confirmed. Sperm viability decreases with increasing cell phone exposure.
Concentration is the number of sperm per ml of ejaculate. The assumption is that the higher the concentration, the higher the likelihood of fertilization. Six studies were pooled for the meta-analysis, two in vivo groups, and four in vitro groups. The results were not statistically conclusive for this particular quality. More studies need to be conducted to determine if RF-EMF has an effect on concentration, or whether other factors, such as the heat emitted from cell phones may cause a change in sperm concentration.
Studies show that cell phone use has adverse effects including headaches, increasing resting blood pressure, and creating electroencephalographic (EEG) sleep disturbances. Thermal and non-thermal interactions with body tissues are clearly evidenced. While further study is indicated, this meta-analysis offers supportive evidence that sperm motility and viability is adversely affected by cell phone exposure, potentially exacerbating problems for males experiencing fertility difficulties.