Background: Pervasive healthcare is a new paradigm of healthcare services where the patients are active participants on their own well being. The development of Pervasive Healthcare Systems (PHSs) consists on approaching monitoring solutions into the hands of the patients, and has been reported as a key to minimize the healthcare costs due to the aging of population. However, interoperability is a technological challenge not taken into account in most of the existing implementations of PHSs. Objectives: This paper focuses on how we provide interoperability to a PHS for the management of the gestational diabetes mellitus (GDM) by using the CDA standard. In this monitoring system an Android application sends CDA documents to the server side of the system, so that the health information reported by the patient is transmitted over the Internet in an interoperable way.