Types of Problems
The Electric Blanket Institute explains that a heated mattress pad poses the same risk of overheating as any other electrical appliance. If the cord becomes trapped between the mattress and box spring, it is subjected to friction that causes damage and increases the chance a fire will occur. Similarly, if the mattress pad bunches, heat cannot escape and users may burn themselves.
Users with Increased Risks
Electric bedding manufacturer Sunbeam cautions against using a heated mattress pad for infants, children or immobile users, including paraplegics and quadriplegics, because they cannot safely operate the mattress pad or its controls. Sunbeam also warns that diabetics experiencing a reduced sensitivity to heat may risk burning themselves when using a heated mattress pad or similar device. Pregnant women using heated mattress pads risk harming the fetus, especially if the pad overheats.
Controversy
Beginning in the 1980s, some researchers became concerned regarding electromagnetic frequency waves, or EMFs, which are created by overhead power lines and some electrical appliances. While some scientists claim that EMFs cause cancer and adversely effect reproduction, cognition and behavior, results were largely inconclusive. Still, experts often warn about the damaging effects caused by EMFs and warn about using any electrical appliance excessively, including heated mattress pads.