Summary

Diabetes in pregnancy can be pre-existing (that is, type 1 or type 2 diabetes), or might arise as a result of the pregnancy (gestational diabetes). It is known to adversely affect mothers and their babies during pregnancy, labour and delivery. The type and severity of complications experienced by mothers and their babies differs by maternal diabetes type.

Diabetes affects nearly 1 in 10 pregnancies

In the 2-year period from 2014–2015, more than 45,000 mothers who gave birth in Australia (excluding Victoria) had diabetes, representing about 9.9% of all births recorded in the National Perinatal Data Collection (NPDC). Of those, about 40,500 (8.9%) had gestational diabetes, and 4,700 (1.0%) had pre-existing diabetes (Supplementary Table 1.1).

Mothers with pre-existing diabetes were at highest risk of adverse effects

Compared with mothers with no diabetes in pregnancy, mothers with pre-existing diabetes and gestational diabetes had higher rates of caesarean section, induced labour, pre-existing and gestational hypertension, and pre-eclampsia. They also had longer antenatal and postnatal stay in hospital (5 or more days).

Mothers with gestational diabetes experienced complications at a lower rate than mothers with pre-existing diabetes.

Babies of mothers with pre-existing diabetes were at highest risk of adverse effects

Compared with babies of mothers with gestational diabetes or no diabetes, babies of mothers with pre-existing diabetes had higher rates of pre-term birth, stillbirth, low and high birthweight, low Apgar score, resuscitation, and special care nursery/ neonatal intensive care unit admission, and stayed longer in hospital.

Babies of mothers with gestational diabetes had higher rates of complications than babies of mothers with no diabetes, but showed similar levels of risk as babies of mothers with no diabetes for high birthweight and low Apgar score.

Having diabetes in pregnancy increased the risk of complications among some population groups

Among Aboriginal and Torres Strait Islander mothers, the incidence of some complications occurred at a greater rate among mothers with pre-existing diabetes than among mothers  with no diabetes. Babies of Indigenous mothers with pre-existing and gestational diabetes also experienced greater rates of complications than babies of Indigenous mothers with no diabetes.

In Remote/Very remote areas, mothers with pre-existing and gestational diabetes and their babies experienced greater rates of some complications than mothers with no diabetes and their babies.