Maternal deaths

Maternal deaths in Australia

The maternal mortality rate in Australia in 2021 was 5.8 deaths per 100,000 women giving birth (18 maternal deaths).

In the decade from 2012 to 2021, there were 191 women reported to have died during pregnancy or within 42 days of the end of pregnancy and a maternal mortality rate of 6.3 deaths per 100,000 women giving birth. These deaths are reviewed in this article along with contextual information for maternal deaths in Australia since 2012.

In Australia, where childbirth is safe for most women, maternal death is rare. All maternal deaths are reviewed by health professionals to determine the likely cause and whether the pregnancy contributed to the death.

Definitions

Maternal death is the death of a woman while pregnant or within 42 days of the end of pregnancy, irrespective of the duration and outcome of the pregnancy, from any cause related to or aggravated by the pregnancy or its management but not from accidental or incidental causes.

Maternal deaths are divided into two categories, direct and indirect. Direct maternal deaths are those resulting from obstetric complications of pregnancy or its management. Indirect maternal deaths are those resulting from diseases or conditions that were not due to a direct obstetric cause, but were aggravated by the physiologic effects of pregnancy. Deaths considered to be causally unrelated to pregnancy are classified as coincidental (see below for more information on these deaths).

Coincidental deaths are defined as those that are reported to have occurred during pregnancy or within 42 days of the end of pregnancy, but are considered to be causally unrelated to pregnancy. Unlike direct and indirect maternal deaths, coincidental deaths are excluded from analysis and maternal mortality ratio (MMR) calculations.

There were 54 coincidental deaths in Australia from 2012–2021. The most common causes of these deaths were motor vehicle trauma and cancer. Detailed data on causes and timing of maternal deaths can be found in Tables 1, 2 & 3 of the supplementary tables (Data tables: National Maternal Mortality Data Collection annual update 2021).

Figure 1: Maternal deaths in Australia, 2021

Maternal mortality over time

The incidence of maternal death is expressed as the maternal mortality ratio (MMR). The MMR is calculated using direct, indirect and not classified maternal deaths and expressed as per 100,000 women giving birth. Coincidental deaths and deaths awaiting classification are not included in MMR calculations. Between 2012 and 2021, the MMR in Australia was relatively stable, ranging from between 5.2 to 8.4 per 100,000 women giving birth. Fluctuations appear to reflect the normal variability that might be expected with rare events such as maternal deaths.

Data on maternal mortality ratios over time can be explored in the interactive data visualisation below, with data also presented in Table 1 of the supplementary data tables (Data tables: National Maternal Mortality Data Collection annual update 2021).

Figure 2: Maternal mortality ratio of women who gave birth, 2012–2021

Causes of maternal deaths

The most frequent causes of maternal death reported in Australia between 2012 and 2021 were:

• For all maternal deaths:
  • cardiovascular disease (26 deaths or 14%)
  • sepsis (21 deaths or 11%).
  • thromboembolism (20 deaths or 10%)
  • suicide (20 deaths or 10%)
• For direct maternal deaths:
  • thromboembolism (19 deaths)
  • amniotic fluid embolism (14 deaths)
  • sepsis (12 deaths)
• For indirect maternal deaths:
  • complications of pre-existing cardiovascular disease (22 deaths)
  • non-obstetric haemorrhage (mostly haemorrhage within the brain and haemorrhage from a ruptured aneurysm of the splenic artery) (14 deaths)
  • suicide (12 deaths).

Data on causes of maternal deaths from 2012–2021 can be explored in the interactive visualisation below, with data also presented in Table 2 of the supplementary data tables (Data tables: National Maternal Mortality Data Collection annual update 2021).

Figure 3: Number of maternal deaths, by cause of death, 2012–2021

Timing of maternal deaths

Understanding the timing of maternal deaths is important for identifying periods of critical risk. Between 2012 and 2021:

• More than 1 in 3 (37%) maternal deaths occurred in women who were pregnant at the time of their death.
• 2 in 5 women (40%) who were pregnant at the time of death died during the first trimester of pregnancy (less than 14 weeks of pregnancy).
• 1 in 5 (19%) maternal deaths occurred during the birth process or within 24 hours of giving birth.
• More than 2 in 5 (44%) maternal deaths occurred after the woman gave birth, with more than half (58%) of these deaths occurring within 1 to 13 days of giving birth.

Between 2012 and 2021, the timing of maternal death was known for 162 (85%) of the 191 deaths. The proportions for the timing of maternal deaths calculated above exclude maternal deaths where timing is not stated or unknown (20 deaths, 10%). Maternal deaths following or due to miscarriage or termination of pregnancy are also excluded, as timing of death is not routinely reported for these cases (9 deaths, 4.7%).

Data on the timing of maternal deaths between 2012 and 2021 can be explored in the interactive visualisation below, with data also presented in Table 3 of the supplementary data tables (Data tables: National Maternal Mortality Data Collection annual update 2021).

Figure 4: Number of maternal deaths, by timing of death, 2012–2021

Characteristics of women who died

This section presents some demographic characteristics of the women who died from 2012–2021. It should be noted that not all demographic information was available for all women who died. Caution should be used when interpreting these data, due to the small number of maternal deaths in Australia, and even smaller numbers when these deaths are broken down by characteristics.

Maternal age

Women aged under 20 had the highest MMR, followed by those aged 40 or more (17.4 and 11.3 per 100,000 women giving birth). The lowest MMR was for women in the 20 to 24 age group, followed by women in the 25 to 29 age group (1.9 and 4.7 per 100,000 women giving birth respectively).

Maternal Indigenous status

In the period 2012–2021, there were 21 maternal deaths among Aboriginal and Torres Strait Islander (First Nations) women, and the MMR for First Nations women was 16.8 per 100,000 women giving birth. In the same period, the MMR for non-Indigenous women was 5.3 per 100,000 women giving birth.

Parity

Parity refers to a woman’s number of previous pregnancies, excluding the current pregnancy, carried to a viable gestational age (usually 20 weeks). The rate of maternal death broadly increased with parity, from an MMR of 4.8 and 4.3 per 100,000 women giving birth for women with a parity of 0 and 1 respectively, increasing up to 11.3 for women with a parity of 3 and 18.4 for women with a parity of 4 or more.

Smoking status

The rate of maternal deaths was higher in women who reported smoking during the first 20 weeks of pregnancy than in women who reported that they did not smoke during the first 20 weeks of pregnancy (15.7 compared to 3.7 per 100,000 women giving birth). As the number of maternal deaths with an unknown smoking status is relatively high (32% of data from included jurisdictions), caution should be used when interpreting these data.

Remoteness

Women who lived in Remote and Very remote areas had the highest MMR, followed by women who lived in Inner regional areas (14.8 and 7.9 per 100,000 women giving birth). The lowest MMR was for women who lived in Major cities (5.6 per 100,000 women giving birth). The rate of maternal death in areas other than Major cities should be treated with caution due to the small numbers.

Data on maternal deaths by selected maternal characteristics from 2012–2021 can be explored in the interactive visualisation below, with data also presented in Tables 48 of the supplementary data tables (Data tables: National Maternal Mortality Data Collection annual update 2021).

Figure 4: Maternal mortality ratio of women who gave birth, by selected maternal characteristic, 2012–2021

Australia's mothers and babies