Background : Information systems allow for the availability of clinical records in computer databases. Obstetric caring demands a continuous process of information sharing between health professionals. However, the lack of communication between points of assistance has allowed for an accumulation of local data without the benefits of data interoperability. Objective : The study’s objective is to develop an information model with essential obstetric data to reuse information from primary sources through to tertiary level of care, and to foster the continuity of information. Methods : An exploratory research involved focus group discussions with obstetricians as domain specialists and computer scientists. Fictitious cases of obstetric emergencies were discussed to select meaningful information from prenatal care for the specialists’ decision making. Ninety electronic medical records (EMR) from a university obstetric emergency unit were used to validate the information model. A second-round evaluation with the obstetrician met the specialists' requirements, the information model was also finalized after adjustments to semantic standards and the structure of the clinical data. Results: The study found a recurring set of clinical information that was common in both the domain specialist requests and the EMR retrospective analysis. However, the lack of informational standards, use of acronyms and abbreviations characterized real histories in the obstetric EMR. The minimum antenatal dataset entries was structured into nine sections, and fifty-six data entries. Conclusion : The development of an information model for the continuity of care records, based on the standard of interoperability and usefulness for clinicians, has the potential to overcome the informality of EMR.