The aim of this study was to compare the quality of the reporting and coding of eclampsia in two routine data collections: the Victorian Inpatient Minimum Database (VIMD) and the Perinatal Data Collection Unit (PDCU). The validity of cases in the two data sets was confirmed by reference to the original medical record data. Only 12 cases were the same in both data sets (i.e., 35.3% agreement). There were an additional 51 cases that were reported to either one or the other of the data sets and, of these, only 15 (i.e., 29%) were confirmed as eclampsia. The overall number of cases confirmed for both systems in 1995 was 27, or 0.4 per 1000 confinements. Reasons for these discrepancies were investigated and three basic problems identified: quality of documentation in the medical record, coding errors, and use of data from computer-generated forms. Neither the VIMD nor the PDCU was regarded as having sufficiently accurate data for adequate reporting of maternal morbidity. By combining the information from both databases a better estimate of incidence can be obtained, but improved reporting and coding is essential for accurate assessment of this condition.