Hypertension in pregnancy
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Hypertensive disorders of pregnancy
- Nearly 16,300 women (5.9%) aged 15–44 who gave birth in Australia had a hypertensive disorder of pregnancy in 2023.
- Among these women, gestational hypertension and pre-eclampsia were the most common hypertensive disorders of pregnancy.
- The highest proportion of hypertensive disorders of pregnancy was reported for women aged 40–44 (9.2%) and the lowest was reported for those aged 30–34 (5.3%).
Incidence of hypertension in pregnancy
- In 2023, almost 13,400 women aged 15–44, who gave birth in Australia, had new onset hypertension in pregnancy, an incidence of 4.9%.
- Incidence of hypertension in pregnancy was highest among women aged 40–44 (6.5%) and lowest among those aged 30–34 (4.4%).
Hypertension is a leading cause of illness and death for mothers and babies (RANZCOG 2024). Complications of hypertension that can affect the mother include cardiac problems, cerebral injury, liver and kidney failure. Those which can affect the baby include being born pre-term, being small for gestational age and being admitted to the special care nursery (Fowosere 2024; Queensland Clinical Guidelines 2021).
Hypertensive disorders of pregnancy
Hypertension in pregnancy is defined as systolic blood pressure greater than or equal to 140 mmHg and/or diastolic blood pressure greater than or equal to 90 mmHg confirmed with repeated readings. Hypertensive disorders of pregnancy are conditions associated with hypertension in pregnancy. These include:
Chronic (pre-existing) hypertension is high blood pressure that is present before pregnancy or is diagnosed before 20 weeks’ gestation. Some women may have had high blood pressure before becoming pregnant but were unaware until they got their blood pressure checked at their antenatal visit. Chronic hypertension can be primary (of unknown cause) or secondary (due to a secondary cause such as chronic kidney disease, renal artery stenosis, systemic diseases or endocrine disorders). Chronic hypertension can lead to pre-eclampsia.
Gestational hypertension is new onset of hypertension after 20 weeks’ gestation without any features of pre-eclampsia, followed by the return to normal blood pressure within 3 months postpartum. Gestational hypertension is associated with an increased risk of developing pre-eclampsia as well as the future development of cardiovascular disease (SOMANZ 2023).
Pre-eclampsia is defined as new onset of hypertension after 20 weeks’ gestation accompanied by other symptoms including protein in urine (proteinuria) and involvement of one or more other organ systems and/or the foetus. Onset of seizures in women with pre-eclampsia is called eclampsia. Pre-eclampsia can be serious or even life-threatening for both mother and baby (RANZCOG 2024).
Information on hypertensive disorders of pregnancy presented in this report was obtained from the AIHW’s National Perinatal Data Collection (NPDC). The NPDC is a national population-based dataset which collates data on the pregnancy and childbirth of mothers, and the characteristics and outcomes of their babies. Definitions and data collection methods for pregnancy hypertensive disorders in the NPDC vary across jurisdictions (AIHW 2025). Data for the Australian Capital Territory (ACT) were not available for this analysis. For more information see National Perinatal Data Collection.
Hypertensive disorders of pregnancy
According to the NPDC, nearly 16,300 women aged 15–44 who gave birth in Australia (excluding the Australian Capital Territory) had a hypertensive disorder of pregnancy recorded in 2023.
Of these:
- 53% had gestational hypertension
- 45% had pre-eclampsia
- 15% had chronic (pre-existing) hypertension
- 1.1% had unspecified maternal hypertension
- 0.7% had eclampsia.
Note that some women had more than one of the hypertensive disorders of pregnancy recorded and the total per cent exceeds 100.
How common are hypertensive disorders of pregnancy in Australia?
In 2023, 5.9% of women aged 15–44 who gave birth in Australia had a hypertensive disorder of pregnancy.
Variation by age
Among women who gave birth in Australia in 2023, the highest proportion of hypertensive disorders of pregnancy was reported for women aged 40–44 (9.2%) and the lowest was reported for those aged 30–34 (5.3%) (Figure 7).
Figure 7: Proportion of women with hypertensive disorders of pregnancy among those who gave birth, by age group, 2023
The column chart shows rates for hypertensive disorders of pregnancy were similar among women aged 15–29 years.
| Age group | Data |
|---|---|
| 15–19 | 6.0% |
| 20–24 | 6.0% |
| 25–29 | 5.9% |
| 30–34 | 5.3% |
| 35–39 | 6.3% |
| 40–44 | 9.2% |
Notes
- Population is women aged 15–44 who gave birth in Australia.
- Data for the Australian Capital Territory (ACT) are not included in this analysis as some data for ACT are not available due to a major change in the collection of ACT's health data.
- People whose hypertensive disorders of pregnancy status is unknown ('Not stated') are included in the denominator.
Source:
AIHW analysis of National Perinatal Data Collection.
|
Data source overview
Variation by priority population groups
Remoteness area
In 2023, after adjusting for differences in the age structure of the populations, the proportion of women with hypertensive disorders of pregnancy was 1.3 times as high among women living in Inner regional and outer regional areas, and 1.2 times as high in those living in Remote and very remote areas when compared to those living in Major cities (Figure 8).
Socioeconomic area
In 2023, after adjusting for age differences in the populations, the proportion of women with hypertensive disorders of pregnancy increased with increasing socioeconomic disadvantage. The proportion of women with hypertensive disorders of pregnancy among those living in the 2 lowest socioeconomic areas was 1.5 times as high as that for those living in the highest socioeconomic areas (Figure 8).
Figure 8: Proportion of women with hypertensive disorders of pregnancy among those who gave birth, by selected population group, 2023
The chart shows rates for hypertensive disorders of pregnancy were lowest in women living in Major cities (6.0%) and those in the least disadvantaged areas (4.8%).
| Remoteness area | Data |
|---|---|
| Major cities | 6.0% |
| Inner regional | 7.6% |
| Outer regional | 7.6% |
| Remote and very remote | 7.5% |
| Socioeconomic area | Data |
|---|---|
| Group 1 (most disadvantaged) | 7.4% |
| Group 2 | 7.4% |
| Group 3 | 6.5% |
| Group 4 | 6.1% |
| Group 5 (least disadvantaged) | 4.8% |
- Age-standardised to the 30 June 2001 Australian female resident population aged 15–44.
- Population is women aged 15–44 who gave birth in Australia.
- Data for the Australian Capital Territory (ACT) are not included in this analysis as some data for ACT are not available due to a major change in the collection of ACT's health data.
- Excludes persons whose remoteness area or socioeconomic area was missing or not stated.
- People whose hypertensive disorders of pregnancy status is unknown ('Not stated') are included in the denominator.
- Remoteness is classified according to the ASGS Remoteness Areas structure based on 2021 Statistical Area Level 2 (SA2) of usual residence.
- Socioeconomic groups are classified according to the Index of Relative Socio-Economic Disadvantage quintiles based on 2021 ASGS Statistical Area Level 2 (SA2) of usual residence.
Source:
AIHW analysis of National Perinatal Data Collection..
|
Data source overview
Country of birth
In 2023, after adjusting for differences in the age structure of the populations, the proportions of hypertensive disorders of pregnancy were:
- highest for women who were born in Oceania and Antarctica (7.5%) and Australia (7.1%)
- lowest for women who were born in Southern and Eastern Europe (3.2%) and North Africa and Middle East (3.8%) (Figure 9).
For detailed information on hypertension by country of birth, see Australia's mothers and babies.
Figure 9: Proportion of women with hypertensive disorders of pregnancy among those who gave birth, by country of birth, 2023
The chart shows that rates for hypertensive disorders of pregnancy were highest in women born in Oceania and Antarctica (7.1%) and lowest in those born in Southern and Eastern Europe (3.2%).
| Country of birth | Data |
|---|---|
| Oceania and Antarctica | 7.5% |
| Australia | 7.1% |
| Sub-Saharan Africa | 6.0% |
| North-East Asia | 5.1% |
| South-East Asia | 5.1% |
| Southern and Central Asia | 4.5% |
| North-West Europe | 4.4% |
| Americas | 4.3% |
| North Africa and the Middle East | 3.8% |
| Southern and Eastern Europe | 3.2% |
- Age-standardised to the 30 June 2001 Australian female resident population aged 15–44.
- Population is women aged 15–44 who gave birth in Australia.
- Data for the Australian Capital Territory (ACT) are not included in this analysis as some data for ACT are not available due to a major change in the collection of ACT's health data.
- Excludes persons whose birth country was missing or not stated.
- People whose hypertensive disorders of pregnancy status is unknown ('Not stated') are included in the denominator.
- Country of birth is classified using major groupings from the ABS 2016 Standard Australian Classification of Countries (SACC).
Source:
AIHW analysis of National Perinatal Data Collection.
|
Data source overview
For information about First Nations people, see Aboriginal and Torres Strait Islander (First Nations) people.
How common is new onset hypertension in pregnancy in Australia?
In this report, new onset (incident) hypertension in pregnancy is defined as having:
- gestational hypertension or
- pre-eclampsia/eclampsia without pre-existing hypertension recorded.
In 2023, nearly 13,400 women aged 15–44 who gave birth in Australia had new onset hypertension in pregnancy, equating to about 1 in 20 women (4.9%) who gave birth.
Variation by age
In 2023, the incidence of hypertension in pregnancy was:
- highest among women aged 40–44 (6.5%) and those aged 15–19 (5.7%) and
- lowest among women aged 30–34 (4.4%) (Figure 10).
Figure 10: Incidence of hypertension in pregnancy among women who gave birth, by age group, 2023
The chart shows incidence of hypertension in pregnancy was highest in women aged 40–44 and lowest in those aged 30–34.
| Age group | Data |
|---|---|
| 15–19 | 5.7% |
| 20–24 | 5.4% |
| 25–29 | 5.1% |
| 30–34 | 4.4% |
| 35–39 | 4.8% |
| 40–44 | 6.5% |
- Population is women aged 15–44 who gave birth in Australia.
- Data for the Australian Capital Territory (ACT) are not included in this analysis as some data for ACT are not available due to a major change in the collection of ACT's health data.
- New onset hypertension includes gestational hypertension and/or preeclampsia/eclampsia (excluding chronic hypertension).
- People whose hypertensive disorders of pregnancy status is unknown ('Not stated') are included in the denominator.
Source:
AIHW analysis of National Perinatal Data Collection.
|
Data source overview
Variation by priority population groups
Remoteness area
In 2023, compared to women living in Major cities, the age-standardised incidence of hypertension in pregnancy was 1.3 times as high among those living in Inner regional areas and 1.2 times as high for those living in Outer regional areas and Remote and very remote areas (Figure 11).
Socioeconomic area
In 2023, the age-standardised incidence of hypertension in pregnancy among women living in the 2 lowest socioeconomic areas was 1.4 and 1.5 times as high as that for those living in the highest socioeconomic areas (Figure 11).
Figure 11: Incidence of hypertension in pregnancy among women who gave birth, by selected population groups, 2023
The chart shows highest incidence in women living in Major cities (4.9%) and those living in the least disadvantaged areas (4.1%).
| Remoteness area | Data |
|---|---|
| Major cities | 4.9% |
| Inner regional | 6.3% |
| Outer regional | 6.1% |
| Remote and very remote | 5.7% |
| Socioeconomic area | Data |
|---|---|
| Group 1 (most disadvantaged) | 5.7% |
| Group 2 | 6.1% |
| Group 3 | 5.2% |
| Group 4 | 5.1% |
| Group 5 (least disadvantaged) | 4.1% |
- Age-standardised to the 30 June 2001 Australian female resident population aged 15–44.
- Population is women aged 15–44 who gave birth in Australia.
- Data for the Australian Capital Territory (ACT) are not included in this analysis as some data for ACT are not available due to a major change in the collection of ACT's health data.
- New onset hypertension includes gestational hypertension and/or preeclampsia/eclampsia (excluding chronic hypertension).
- People whose hypertensive disorders of pregnancy status is unknown ('Not stated') are included in the denominator.
- Excludes persons whose remoteness area or socioeconomic area was missing or not stated.
- Remoteness is classified according to the ASGS Remoteness Areas structure based on 2021 Statistical Area Level 2 (SA2) of usual residence.
- Socioeconomic groups are classified according to the Index of Relative Socio-Economic Disadvantage quintiles based on 2021 ASGS Statistical Area Level 2 (SA2) of usual residence.
Source:
AIHW analysis of National Perinatal Data Collection.
|
Data source overview
Country of birth
In 2023, after adjusting for differences in the age structure of the populations, the incidence of hypertension in pregnancy was:
- highest for women who were born in Oceania and Antarctica, such as New Zealand, Fiji, Tonga and Papua New Guinea (6.0%) and Australia (5.9%)
- lowest in women who were born in North Africa and the Middle East (3.0%) and Southern and Eastern Europe (2.3%) (Figure 12).
Figure 12: Incidence of hypertension in pregnancy among women who gave birth, by country of birth, 2023
The chart shows that incidence was highest in women born in Oceania and Antarctica (6.0%) and lowest in those born in Southern and Eastern Europe (2.3%).
| Country of birth | Data |
|---|---|
| Oceania and Antarctica | 6.0% |
| Australia | 5.9% |
| Sub-Saharan Africa | 4.8% |
| North-East Asia | 4.6% |
| South-East Asia | 3.8% |
| North-West Europe | 3.7% |
| Americas | 3.6% |
| Southern and Central Asia | 3.3% |
| North Africa and the Middle East | 3.0% |
| Southern and Eastern Europe | 2.3% |
- Age-standardised to the 30 June 2001 Australian female resident population aged 15–44.
- Population is women aged 15–44 who gave birth in Australia.
- Data for the Australian Capital Territory (ACT) are not included in this analysis as some data for ACT are not available due to a major change in the collection of ACT's health data.
- New onset hypertension includes gestational hypertension and/or preeclampsia/eclampsia (excluding chronic hypertension).
- People whose hypertensive disorders of pregnancy status is unknown ('Not stated') are included in the denominator.
- Excludes persons whose birth country was missing or not stated.
- Country of birth is classified using major groupings from the ABS 2016 Standard Australian Classification of Countries (SACC).
Source:
AIHW analysis of National Perinatal Data Collection.
|
Data source overview
For information about First Nations people, see Aboriginal and Torres Strait Islander (First Nations) people.
For more information on hypertension in pregnancy, see the report on Australia's mothers and babies.
AIHW) (2025) Australia's mothers and babies, AIHW, Australian Government, accessed 16 September 2025.
Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) (2024) Early pregnancy screening and prevention of preterm preeclampsia and related complications (C-Obs 61), RANZCOG Statements and guidelines, Obstetrics, RANZCOG, accessed 19 September 2025.
Society of Obstetric Medicine of Australia and New Zealand (SOMANZ) (2023) Hypertension in Pregnancy Guideline, SOMANZ, accessed 16 September 2025.
Fowosere V (2024) ‘Hypertensive disorders in pregnancy: Approach to diagnosis and management in general practice’, Australian Journal of General Practice, 53(12):52–55, doi:10.31128/AJGP-01-24-7133.
Queensland Clinical Guidelines (2021) Hypertension and pregnancy, Queensland Health, Australian Government, accessed 18 March 2026.