Reporting postpartum haemorrhage with transfusion: a comparison of NSW birth and hospital data

Postpartum haemorrhage rates have been increasing in NSW and internationally, and blood transfusion is required in severe cases. Using routinely collected administrative data provides a convenient method with which to monitor trends in both postpartum haemorrhage and associated transfusion use. In order for this to be feasible however, the reliability of reporting of the conditions needs to be assessed.

This study used linked data to compare the reporting of postpartum haemorrhage with transfusion as reported in the NSW Admitted Patient Data Collection (hospital data), with the same information obtained from the Perinatal Data Collection (birth data), for births in NSW from 2007 to 2010.

The rate of postpartum haemorrhage requiring blood transfusion was 1.0% based on the hospital data and 1.1% based on the birth data, with a rate of 1.7% if identifying cases from either source. Agreement between the two sources improved from fair to moderate over the time period.

Postpartum haemorrhage requiring transfusion recorded in the birth data shows only moderate agreement with hospital data, so caution is recommended when using this variable for analysis. Linkage of both datasets is recommended to identify birth information from birth data and postpartum haemorrhage with transfusion from hospital data until further validation work has been undertaken.