Yes, the information transferred between the base unit (the phone’s stationary unit) and the wireless phone’s mobile unit is transferred as radiowave radiation. Therefore, the “precautionary principle” should also be adopted regarding wireless phones. In addition to the guidelines regarding mobile phones, the Ministry of Health recommends regarding wireless phones:
The authors found a consistent effect, in both types of studies, that cellphone radiation leads to decreased sperm motility (ability to swim) and viability, but not a decrease in overall concentration. While it’s unclear if these specific changes are enough to affect men’s fertility, the authors wrote, “mobile phone exposure may form part of a cumulative effect of modern day environmental exposures, that collectively reduce sperm quality and explain current trends in infertility.”

If you want to use your phone for talking, then the idea is that you keep it flipped over the front of the screen – that way you’re blocking radiation on both the front and back. The speaker still works with the cover on, because there’s a small hole for that. The inevitable drawback of this is that you have to flip the cover open in order to access your keypad.
Yes, cell phones emit Electromagnetic Fields (EMF) and direct exposure to these emissions can be a health risk. There are two types of EMF radiation emitted from cell phones: Extremely Low Frequency (ELF) radiation and Radio Frequency (RF) radiation (which includes cellular signals, WiFi and Bluetooth). More and more, particularly in recent years, scientific studies have confirmed that these EMF exposure can adversely modify the biological operations of the body. In more serious cases, exposure to EMFs can lead to tumors, reduce sperm count and other serious health concerns.
The energy of electromagnetic radiation is determined by its frequency; ionizing radiation is high frequency, and therefore high energy, whereas non-ionizing radiation is low frequency, and therefore low energy. The NCI fact sheet Electromagnetic Fields and Cancer lists sources of radiofrequency radiation. More information about ionizing radiation can be found on the Radiation page.