Maternal medical conditions

Diabetes and hypertension (high blood pressure) are significant sources of maternal illness and death. Pregnant women with pre-existing or gestational diabetes or pre-existing or gestational hypertension disorders have increased risk of developing adverse outcomes in pregnancy.

Please note that data collection methods for diabetes and hypertension vary across states and territories, and data exclude Victoria.

Diabetes

Diabetes affecting pregnancy can be pre-existing (that is, type 1 or type 2) or may arise as a result of the pregnancy (gestational diabetes) (AIHW 2019). It can have short-term and long-term implications for both mothers and their babies and the type and severity of complications may differ according to type of diabetes experienced in pregnancy (AIHW 2019).

Monitoring diabetes during pregnancy is important as it provides information on the impact of diabetes during pregnancy and its complications, identifies groups at higher risk and assists with the planning, monitoring and provision of services (AIHW 2019).

The figure shows a bar chart of maternal diabetes status by a range of topics in 2019 and a line graph of topic trends between 2014 and 2019. In 2019, 33,867 women, or 11%, had gestational diabetes.

Since 2014, the proportion of women with gestational diabetes has been increasing (8.3% in 2014 compared with 13.5% in 2019).

In 2019, older mothers were more likely to have gestational diabetes (17.8% among mothers aged 40 and over compared with 5.0% for those aged under 20) or pre-existing diabetes (including types 1 and type 2 diabetes) (1.7% among mothers aged 40 and over compared with 0.4% for those aged under 20).

Pre-existing and gestational diabetes increased with the number of previous pregnancies (for example, from 11% among mothers with no previous pregnancies to 15% among mothers with four or more previous pregnancies). However, this pattern may be affected by maternal age, as women who have had more pregnancies are likely to be older on average than those with fewer pregnancies.

Hypertension

Hypertension is a leading cause of illness and death for mothers and babies (Queensland Clinical Guidelines 2015). Complications of hypertension that can affect the mother include cerebral injury, liver and kidney failure and those which can affect the baby include being born pre-term, being small for gestational age and being admitted to the special care nursery (Queensland Clinical Guidelines 2015).

The figure shows a bar chart of women who gave birth by hypertension status by a range of topics for 2019 and a line graph of topic trends between 2014 and 2019. In 2019, 7,420 women, or 2%, had gestational hypertension.

The proportion of women with gestational hypertension has remained stable at about 3–4% since 2014.

In 2019, older mothers were more likely than younger age groups to have hypertensive disorders (both pre-existing and gestational); for example, 4.4% of mothers aged 40 and over had gestational hypertension compared with 3.1%–3.4% across younger age groups.

First-time mothers (4.4% in 2019) were more likely to have gestational hypertension than those who had given birth previously (ranging from 2.3% for mothers with one previous pregnancy to 2.9% for mothers with four or more). Mothers born in Australia (3.8%) were also more likely to have gestational hypertension than mothers born overseas (2.2%).

References

AIHW (Australian Institute of Health and Welfare) 2019. Diabetes in pregnancy 2014–2015. Bulletin no. 146. Cat. no. CDK 7. Canberra: AIHW.

Queensland Clinical Guidelines 2015. Hypertensive disorders of pregnancy. MN15.13-V7-R20. Brisbane: Queensland Health. Viewed 18 January 2019.