Abstract: A maternity mattress provided with a cavity for accommodating the abdomen of a pregnant woman as she lies upon the mattress in a prone position. The mattress tick includes a removable portion which normally lies conterminously above the cavity to readily expose the cavity. A plurality of resilient disklike members are included and which jointly conform in size and shape with the cavity to normally fill the cavity but which may be removed one at a time as the pregnancy progresses to gradually increase the size of the cavity. A peculiar washable bedsheet preferably is included and which overlies the mattress. The bedsheet includes a pocket which conforms in size and shape with and is disposed conterminously with the cavity thus providing a lining therefor. Provisions are included for removably fastening the removable portion of the mattress tick in place with a protective barrier being added to protect the woman against irritable body contact with the fastening apparatus.