Summary

Diabetes affecting pregnancy can be pre-existing diabetes (that is, type 1, type 2, or other types of diabetes), or might arise as a result of the pregnancy (gestational diabetes), and has serious implications for the health of mothers and babies.

This report:

  • identifies and describes national data sources available for monitoring the effects of diabetes during pregnancy on mothers and babies
  • identifies current data gaps and alternate data sources for monitoring outcomes associated with diabetes during pregnancy
  • explores the feasibility of data linkage to improve the monitoring of outcomes.

Data sources to monitor the impact of diabetes during pregnancy

Data on diabetes in pregnancy are available from various data sources in Australia, all of which have strengths and weaknesses. Three data sources provide data at the national level:

  • The National Perinatal Data Collection (NPDC) is a national population-based collection of data on pregnancy and childbirth. The data collected within the NPDC identify women who gave birth and were found as either having pre-existing diabetes or gestational diabetes during pregnancy, as well as outcomes of these mothers and their babies around the time of birth.
  • The National Hospital Morbidity Database (NHMD) is a collection of episode-level records from the Admitted Patient Care National Minimum Data Set. It contains information on episodes of care for admitted patients in hospital (pregnant women and babies), and includes demographic, diagnostic, outcomes, interventions and procedural information.
  • The National Diabetes Services Scheme (NDSS) is an initiative of the Australian Government, administered with the assistance of Diabetes Australia. The NDSS provides information and support services, and delivers diabetes-related products at subsidised prices to people with diabetes. Within the NDSS, the National Gestational Diabetes Register (NGDR) was established to help women who have had gestational diabetes manage their future health. It contains demographic and some treatment information for women with diabetes.

Other data sources provide information at the state and territory level, or for specific population cohorts, but are not sufficient for exploring the Australian national context.

Improving national reporting

The NPDC is a useful data set to assess the outcomes of mothers and babies affected by diabetes during pregnancy. It enables mothers with diabetes in pregnancy to be identified, and the impact of diabetes on the health of these mothers and their babies to be assessed.

But some factors limit the use of the NPDC in looking at the impact of maternal diabetes on the health of mothers and their babies, including:

  • the inability of some states and territories to distinguish between types of diabetes
  • differences in data collection methods across jurisdictions.

The NHMD contains information about episodes of care for patients in hospital, including pregnant women and babies. But the inaccuracy of recording diabetes type, and changes in the coding of diabetes limit the use of data from the NHMD for reporting outcomes and complications by pre-existing diabetes type.

The NDSS and NGDR contains demographic and some treatment information for women with gestational diabetes, but are not designed to capture pregnancy-related information outside of gestational diabetes status. As such, they cannot be used to assess pre-existing diabetes in pregnancy, or supply information on pregnancy-related complications or outcomes.

Data required to monitor the impact of diabetes in pregnancy, and fill current knowledge gaps are not available in any one data set, but a more comprehensive data set could be obtained by linking multiple data sets containing information on mothers and babies.

Linking a national data set that has a robust record of births in Australia and diabetes in pregnancy status with other data sets containing information on health service use and treatment would provide a more comprehensive data set.