A new study led by Gorpinchenko et al. suggests that mobile phone radiation or cell phone radiation may lower male fertility.  The study finds that sperm samples exposed to mobile phone radiation had fewer sperm with progressive movement and higher DNA fragmentation.  The sperm samples used in the study came from 35 healthy men with normozoospermia.  

Adams et al. meta-analyze data from ten studies of 1492 semen samples and find that exposure to cell phone radiation reduces sperm motility and viability while having no effect on the sperm concentration.

Radio-frequency electromagnetic radiation (RF-EMR) from WiFi devices like mobile phones or cell phones is known to cause oxidative damage to cells, which is linked to cancer and other chronic diseases.

One thing to do to reduce the "side effect" of cell phones or mobile phones is take some antioxidant supplements such as vitamin C and alpha-lipoic acid even though it may not completely prevent the effect.  Ginseng is also known to be protective against the cell phone radiation induced oxidative injury. (David Liu, PHD)

Gorpinchenko I, Nikitin O, Banyra O, Shulyak A.  The influence of direct mobile phone radiation on sperm quality.   Cent European J Urol. 2014;67(1):65-71.

Adams JA, Galloway TS, Mondal D, Esteves SC, Mathews F.  Effect of mobile telephones on sperm quality: A systematic review and meta-analysis.  Environ Int. 2014 Sep;70C:106-112.