Gestational diabetes

Page highlights

How common is gestational diabetes in Australia?

  • Almost 1 in 5 women (18%) who gave birth in 2023–24 was diagnosed with gestational diabetes (49,800 women).
  • Incidence of gestational diabetes increased with increasing maternal age, ranging from 7.4% in women aged 15–19 to 32% in those aged 45–49.
  • the incidence of gestational diabetes in Australia has doubled between 2012–13 and 2023–24, from 9.3% to 18.9%.

Risk factors

The following factors (Nankervis et al. 2014) increase a woman’s risk of developing gestational diabetes:

  • ethnicity: Asian, Indian subcontinent, Aboriginal, Torres Strait Islander, Pacific Islander, Māori, Middle Eastern, non-white African
  • pre-pregnancy body mass index (BMI) >30 kg/m²
  • previous hyperglycaemia in pregnancy
  • previous elevated blood glucose level
  • maternal age ≥40 years
  • family history of diabetes mellitus (close relative with diabetes or a sister with hyperglycaemia in pregnancy)
  • previous macrosomia (baby with birth weight >4500g or >90th percentile)
  • polycystic ovary syndrome
  • medications: corticosteroids, antipsychotics.

Diagnostic criteria

The Australasian Diabetes in Pregnancy Society (ADIPS) guidelines recommend that all women without diabetes already detected in the current pregnancy should undergo a 75 g 2‐hour pregnancy oral glucose tolerance test (POGTT) at 24–28 weeks’ gestation (also known as universal testing). However, women with a previous history of gestational diabetes or an early pregnancy HbA1c level ≥ 6.0–6.4, but without diagnosed diabetes, are advised to undergo a 75 g two‐hour POGTT before 20 weeks’ gestation, ideally between 10 and 14 weeks’ gestation. A diagnosis of gestational diabetes is made based on (Sweeting et al. 2025):

  • fasting plasma glucose ≥5.3–6.9 mmol/L
  • 1-hour plasma glucose (post 75g oral glucose load) ≥10.6 mmol/L
  • 2-hour plasma glucose (post 75g oral glucose load) ≥9.0–11.0 mmol/L.

For more information about screening, diagnosis and classification of gestational diabetes see the Australasian Diabetes in Pregnancy Society (ADIPS) 2025 Consensus Statement.

How common is gestational diabetes in Australia?

In 2023–24, almost 1 in 5 women (18%) aged 15–49 who gave birth in an Australian hospital was diagnosed with gestational diabetes (49,800 females), based on the National Hospital Morbidity Database. 

Variation by age

In 2023–24, the incidence of gestational diabetes increased with increasing maternal age, ranging from 7.4% to 32% in the 15–19 and 45–49 age groups, respectively. Compared with women aged 15–19, those aged 35–39 were 2.9 times as likely to be diagnosed with gestational diabetes while women aged 40–44 and 45–49 were 3.7 and 4.3 times as likely, respectively (Figure 1).

Figure 1: Incidence of gestational diabetes, by age, 2023–24

The chart shows that gestational diabetes is more frequent with increasing maternal age.

Note: Population (women aged 15–49 giving birth in Australian hospitals) based on ICD-10-AM diagnosis code.

Source: AIHW National Hospital Morbidity Database. | Data source overview

After adjusting for changes in the age structure of the population over time, the incidence of gestational diabetes in Australia doubled between 2012–13 and 2023–24, from 9.3% to 18.9%. The highest incidence was recorded in 2021–22 at 19.3% (Figure 2).  

The rising incidence of gestational diabetes in the last decade is likely driven by several factors including increasing maternal age, higher rates of maternal overweight and obesity, and a growing proportion of higher risk ethnic groups in the population (Laurie and McIntyre 2020). The introduction of new diagnostic guidelines across all states and territories between 2011 and 2013 and the establishment of the National Gestational Diabetes Register (NGDR) in 2011 may also have had an impact on rates. Of note, guidelines for the diagnosis of gestational diabetes were updated again in 2025 (Sweeting et al. 2025). 

For further information refer to Incidence of gestational diabetes in Australia – Changing trends.

Figure 2: Incidence of gestational diabetes, 2012–13 to 2023–24

The chart shows the proportion of females diagnosed with gestational diabetes in Australia doubled between 2012–13 and 2023–24.

Notes

  1. Age-standardised to the 2001 Australian Standard Population of females aged 15–49.
  2. Population (women aged 15–49 giving birth in Australian hospitals) based on ICD-10-AM diagnosis code.
  3. Caution should be taken when comparing rates over time as several factors, including changes in diagnostic guidelines are likely to have had an impact on incidence in recent years.    

Source: AIHW National Hospital Morbidity Database. | Data source overview

Variation by priority population groups

Remoteness area

In 2023–24, the age-standardised incidence of gestational diabetes among women living in Major cities was 1.1 times the rate for those living in Inner regional areas but similar to those in Outer regional and Remote and very remote areas (Figure 3).

Socioeconomic area

In 2023–24, the incidence of gestational diabetes increased with increasing levels of socioeconomic disadvantage. After adjusting for differences in the age structure of the populations, women living in the lowest socioeconomic areas were 1.6 times as likely to be diagnosed with gestational diabetes as those living in the highest socioeconomic areas (Figure 3).

Figure 3: Incidence of gestational diabetes, by priority population group, 2023–24

The chart shows incidence was higher for women living in the lowest socioeconomic areas and lower for those in Inner regional areas.

Population group

Source: AIHW National Hospital Morbidity Database. | Data source overview

Country of birth

In 2023–24, after adjusting for differences in the age structure of the populations, compared with women born in Australia:

  • women born in Southern and Central Asia, South–East Asia, North Africa and the Middle East, and North–East Asia were 2.1, 1.7 and 1.5 times as likely to be diagnosed with gestational diabetes, respectively
  • women born in North-West Europe were 0.7 times, those born in the Americas 0.8 times and those born in Southern and Eastern Europe 0.9 times less likely to be diagnosed with gestational diabetes (Figure 4).

Figure 4: Incidence of gestational diabetes, by country of birth, 2023–24

The chart shows incidence was highest for women born in Southern and Central Asia and lowest for North-West Europe (33% and 12%, respectively).

Source: AIHW National Hospital Morbidity Database. | Data source overview

For information for First Nations people see chapter for First Nations people.