It is better to clean your mattress at least once a year in a regular course of maintenance. Nevertheless, it is quite different if you sleep with pets. You need to take a special care of your mattress if you are suffering from asthma or have allergies. Many manufacturers recommend maintaining 2X a significantly low level of irritants in your mattress. If you feel any odors or stains over your mattress, you can go for a cleaning scheduled as soon as possible.