Background

The Closing the Gap Report 2020 ^1,2 called on the Australian state and federal governments to undertake structural reform to support 15 key recommendations that significantly highlight the importance of strengths-based and community-led approaches. A few of which longitudinal studies supporting models of care for perinatal health exist ^{Reference Lloyd-Johnsen, Eades, McNamara, D’Aprano and Goldfeld3} , to effectively enhance and drive positive health and wellbeing outcomes within Aboriginal and Torres Strait Islander communities. Given that there have been slow changes in maternal health outcomes for Aboriginal and Torres Strait Islander women since the Council of Australian Governments announced the Closing the Gap agenda in 2007, it is perhaps not surprising that this report requests a commitment of 10+ years of coordinated cross-sectoral funding to support the National Aboriginal and Torres Strait Islander Health plan ^{4, 5} and a strong focus on maternal and infant health with recommendations for a life-course approach to health care. Key knowledge gaps related to improving perinatal outcomes have been identified in the literature and include but are not limited to: a) insufficient prenatal biomarker/imaging depth in some cohorts ^{Reference Eades, Hackett, Liu, Brown, Coffin and Cass6–Reference Langton and Stanley9} ; b) lack of routine renal screening despite preterm associations ^{Reference Ibiebele, Coory, Boyle, Humphrey, Vlack and Flenady10,Reference Burrow11} ; c) variable early GDM screening and follow-up ^{Reference Comino, Craig and Harris12,Reference Kemp, Grace and Comino13} ; d) inconsistent embedding of mental health and asthma care in antenatal pathways ^{Reference Ashman, Collins and Weatherall14–Reference Straker, Mountain and Jacques16} , ^{Reference Lee, Lumbers and Oldmeadow17–Reference Rae, Weatherall, Blackwell, Pringle, Smith and Lumbers21} ; e) national datasets under-capture racism, cultural safety, access barriers and service design ^{Reference Shannon22–Reference Carson, Dunbar, Chenhall and Bailie24} .

There are many contributing factors to the ongoing inequalities in health experiences and life expectancy, including a long history of colonisation and oppression resulting in a legacy of political, economic and social disadvantage for Aboriginal and Torres Strait Islanders ^{Reference Straker, Mountain and Jacques16,Reference Shannon22,Reference Gracey and King23,Reference Pringle, Lee and Weatherall25–Reference Najman, Bor, O’Callaghan, Williams, Aird and Shuttlewood27} . Colonisation and the subsequent dispossession and forced removal of children have had significantly traumatising impacts on families and women specifically ^{Reference Chamberlain, Anderson, Fredericks, Calma and Eades7,Reference Carson, Dunbar, Chenhall and Bailie24} . This community legacy of trauma has unique impacts on mental and physical health of women across the life course but particularly during the perinatal period and the subsequent birth outcomes seen in Aboriginal and Torres Strait Islander communities. Institutional racism and the social determinants of health contribute enormously to perinatal outcomes ^{Reference Chamberlain, Anderson, Fredericks, Calma and Eades7,Reference Carson, Dunbar, Chenhall and Bailie24} with many communities facing little to no perinatal care options including antenatal care, ultrasonography and birthing. With many community members living below the poverty line, access to these services can be incredibly stressful and isolating for women and have an impact on nationally reported perinatal outcomes ^{Reference Ibiebele, Coory, Boyle, Humphrey, Vlack and Flenady10,Reference Marriott, Reibel and Coffin28} . Social and economic determinants of health, including structural and historical racism, violence and oppression, institutional neglect and indifference and lack of resources as beforementioned, have led to a decrease in access and utilisation of health services by many Aboriginal and Torres Strait Islander peoples in Australia ^{Reference Gracey and King23,Reference Carson, Dunbar, Chenhall and Bailie24} . This has also been exacerbated by limited delivery of culturally safe and responsive prenatal care, such as early screening for diabetes and tracking of renal function, for this priority population ^{Reference Burrow11,Reference Pringle, Weatherall and Roberts20,Reference Hare, Barzi and Boyle29–Reference Sata, Fukuoka and Hanson31} .

While incredibly valuable, state and national perinatal data is limited in its capacity to understand the breadth of other contributors to perinatal health for Aboriginal and Torres Strait Islander women. There have been a significant number of research projects undertaken with Aboriginal and Torres Strait Islander women during the perinatal period ^{Reference Eades, Hackett, Liu, Brown, Coffin and Cass6,Reference Marriott, Reibel and Coffin28,Reference Mah, Pringle and Weatherall32} , however there are limited studies that have focused on a life-course approach. Current perinatal data collection does not consider some of the specific considerations experienced by Aboriginal and Torres Strait islander women, which may include cultural, geographic and socio-economic determinants ^{Reference Ibiebele, Coory, Boyle, Humphrey, Vlack and Flenady10} . Understanding the unique issues facing Indigenous families and communities is imperative to understanding the context in which perinatal health data exists ^{Reference Gracey and King23,Reference Carson, Dunbar, Chenhall and Bailie24} . Important work by Brown et al. ^{Reference Brown, Gartland and Weetra33} , with Aboriginal women in South Australia (Aboriginal Families Study), highlighted that many Aboriginal and Torres Strait Islander women experience significant racism in their perinatal care that has an associated reduction in healthy birth outcomes. These experiences of racism in care (including delivery of low birth weight infant) showcase other impacts on perinatal outcomes, as well as the importance of trustful relationships between health care professionals and community members. A life course approach such as a longitudinal cohort study approach has been identified as appropriate when working in communities as it allows for a building of the trustful relationship between a participant and a research team that can have lasting impacts on health outcomes over many years ^{Reference Ashman, Collins and Weatherall14,Reference Pringle, Weatherall and Roberts20,Reference Pringle, Lee and Weatherall25} .

Main text

Aboriginal and Torres Strait Islander communities have fought hard to ensure that they can self-determine health initiative programmes and research ^{Reference Eades, Hackett, Liu, Brown, Coffin and Cass6–Reference Eades, Canuto and D.’Antoine8,Reference Kennedy, Maddox, Booth, Maidment, Chamberlain and Bessarab26,Reference Marriott, Reibel and Coffin28} . It has been repeatedly stressed to government, health services and non-Indigenous researchers that Aboriginal and Torres Strait Islander people must lead research, and if, in the instance they choose not to lead, then thorough and embedded consultative processes must be undertaken as a critical step towards a shared research vision ^{2,Reference Eades, Canuto and D.’Antoine8,Reference Langton and Stanley9} . There have been a small number of cohort studies in Australia that have focused on Aboriginal and Torres Strait Islander women during the perinatal period specifically, those studies with deep and rich data for this period, or those that have recruited and reported outcomes for both Aboriginal and Torres Strait Islander women compared with non-Indigenous women as seen in Table 1 (see below).

Table 1.

Summary of Australian perinatal cohorts and programmes with Aboriginal and Torres Strait Islander participants

From the advent of the Mater-University of QLD Study of Pregnancy (MUSP) ^{Reference Najman, Bor, O’Callaghan, Williams, Aird and Shuttlewood27} in the 1980s there have been significant changes in both the political landscape and national ethical guidelines. This makes it unlikely that there was significant undertaking of community consultation with Aboriginal and Torres Strait Islander communities for the MUSP study compared to the most recent studies.

The Raine study was established in Western Australia in 1989 and recruited mothers (who are now known as Gen 1) in pregnancy, their infants (Gen 2; now 28 years) and the grandparents (Gen 0) and any children from Gen 2 who are now referred to as Gen 3 ^{Reference Straker, Mountain and Jacques16} . This multigenerational study has collected data across the life course and has greatly influenced policy and our understanding of drivers for health and disease as a result of perinatal impacts ^{Reference Straker, Mountain and Jacques16,Reference Sayers, Mackerras, Singh, Bucens, Flynn and Reid35} . However, 89.6% of Gen 1 mothers identified as Caucasian, so that limited perinatal information from Aboriginal and Torres Strait Islander women was obtained, and overall retention to the study was limited ^{Reference Straker, Mountain and Jacques16} .

In 1987 to 1990, the first Aboriginal Birth Cohort of Australia was established by the late Dr Susan Sayers at Royal Darwin Hospital (RDH) in the Northern Territory (NT) ^{Reference Sayers, Mackerras and Singh34,Reference Sayers, Mackerras, Singh, Bucens, Flynn and Reid35} . With NT being very sparsely populated and medical care often many hours away it has become common practice for most Aboriginal and Torres Strait Islander women to deliver their infants at RDH. Prior to the study’s establishment, community consultation was undertaken in person by the principal investigator with the larger Aboriginal communities that were close to Darwin, and via telephone with other, more remote communities. This resulted in appropriate letters of endorsement prior to study start. The ABC Study recruited 686 babies from the hospital during this time and have continued to follow the health and wellbeing of these children over time ^{Reference Sayers, Mackerras and Singh34} . At the time of enrolment to the study, perinatal and neonatal data was collected from records. Since enrolment these children have been followed up in a number of waves of data collection (~11 years, 18 years and 25 years) ^{Reference Sayers, Mackerras and Singh34,Reference Sayers, Mackerras, Singh, Bucens, Flynn and Reid35} . Exceptionally, this team has retained approximately 71% of the children in the cohort over 25 years, despite having to travel substantial distances to reconnect at remote outstations and communities across the territory and manage the significant travel challenges that arise during the ‘wet season’ ^{Reference Sayers, Mackerras and Singh34} .

This cohort has at least 30 different Aboriginal languages and dialects being used by participants and for significant cultural reasons this population can be quite mobile. Aboriginal research team members have been an essential part of the study’s success. Ethics has been updated at each wave of the study and has required new community agreements dependent upon the changes to data collection ^{Reference Sayers, Mackerras and Singh34–Reference Sjöholm, Pahkala, Davison, Juonala and Singh36} . With the study having such a lengthy timeline, the research team have strong connected relationships with community locations and families that have greatly aided the richness of the data obtained. Importantly, they also have an Indigenous reference group that the research team work with to obtain guidance on acceptability of planned processes, appropriate contact methods and approaches to providing feedback to participants after their study visits ^{Reference Sjöholm, Pahkala, Davison, Juonala and Singh36} . While the ABC study is an important life-course study for Aboriginal and Torres Strait Islander people, its perinatal health information is limited as recruitment begins from birth rather than during pregnancy.

The Bulundidi Gudaga trial in South-Western Sydney, NSW, Australia recruited in hospital those mothers who identified they had delivered an Aboriginal and/or Torres Strait Islander baby. This study is currently being assessed for effectiveness of the modifications to a perinatal model of care in their region ^{Reference Pringle, Weatherall and Roberts20} . The Gudaga research team have been praised for their engagement and governance that are inclusive of Aboriginal community members ^{Reference Lloyd-Johnsen, Eades, McNamara, D’Aprano and Goldfeld3,Reference Pringle, Weatherall and Roberts20} . They had a large team of Aboriginal and Torres Strait Islander researchers who connected with mothers; clear identification of the study and its team; and strong promotion of the work within the local communities ^{Reference Comino, Craig and Harris12,Reference Kemp, Grace and Comino13} . The team of the Bulundidi Gudaga trial are particularly interested in how a sustained model of home nursing visits can ensure that Aboriginal children’s outcomes are on par with their non-Aboriginal counterparts in the areas of length of breastfeeding, body mass index and developmental outcomes as measured at both 18 months and four years ^{Reference Kemp, Grace and Comino13,Reference Pringle, Weatherall and Roberts20} .

In South Australia, the South Australian Aboriginal Birth Cohort was developed with a focus on perinatal and early childhood interventions to reduce the prevalence of dental caries as well as to monitor a range of childhood developmental outcomes; and included subsequent follow-up of children over a seven year period (to date) ^{Reference Jamieson, Hedges and Ju37} . However, while this cohort has undertaken a randomised controlled trial related to dental health in pregnancy which would likely improve perinatal outcomes, no other data collection occurred during the perinatal period.

The Gomeroi gaaynggal cohort study established with Aboriginal and Torres Strait Islander families in regional New South Wales, Australia, used a life-course holistic approach in both its design and delivery ^{Reference Ashman, Collins and Weatherall14,Reference Pringle, Weatherall and Roberts20,Reference Rae, Weatherall, Blackwell, Pringle, Smith and Lumbers21} . This study undertook a two-year consultation and collaborated with communities to develop a research project that incorporated areas of importance or of need for the local Aboriginal and Torres Strait Islander community. When Gomeroi gaaynggal was initiated (2009), there was maternal health data for Aboriginal and Torres Strait Islander families reported on the prevalence of maternal and birth outcomes for community through national perinatal datasets ^{Reference Ashman, Collins and Weatherall14} , however there was limited information and studies being undertaken about potential associated risk factors or causation of the outcomes. At the request of the local community, these became a major focus of the study. To date, this remains one of the only cohort studies that have sought to develop an understanding of causation of perinatal outcomes. A key priority was to have Aboriginal research staff involved throughout the study, and like other studies this project would not have been a success without their considerable work and passion for the project.

A unique aspect to the Gomeroi gaaynggal study was the initiation of the Gomeroi gaaynggal community ArtsHealth programme that supported cultural arts and health education, with a strong antenatal educational focus ^{Reference Rae, Weatherall, Blackwell, Pringle, Smith and Lumbers21} . This was established and led by local Aboriginal artists who worked within the research centre and collaborated with the research team and diverse health professionals for the health education content. Health professionals included lactation consultants, midwives, dietitians, oral health and Indigenous mental health workers. The ArtsHealth programme worked more broadly across the community than the research programme by including men, school students and Elders and was evidence based. That is, the team focused education activities around nutrition to reduce obesity, and information about supporting healthy kidneys, and other initiatives that built upon research findings to inform community how to best support their own health. The programme assisted with ensuring community continued to engage with research over time and was extremely successful in its art outcomes for its duration, with over 20 art exhibitions some of which toured nationally and internationally ^{Reference Pringle, Weatherall and Roberts20,Reference Rae, Weatherall, Blackwell, Pringle, Smith and Lumbers21} .

From these origins, it is therefore not surprising that Lloyd-Johnsen et al. ^{Reference Lloyd-Johnsen, Eades, McNamara, D’Aprano and Goldfeld3} , reported in their systematic review, that the Gomeroi gaaynggal cohort was identified as a study that undertook community consultation, incorporated Indigenous governance and had a strong Indigenous workforce embedded in its design ^{Reference Ashman, Collins and Weatherall14} . Lloyd- Johnsen also highlighted that cohort studies within Indigenous communities have additional benefits in their capacity for capturing data on early origins of chronic disease for Indigenous communities that incorporate the family, community and society context and can implement a holistic framework to their study designs ^{Reference Lloyd-Johnsen, Eades, McNamara, D’Aprano and Goldfeld3} .

As we are seeing in maternal populations globally, the Gomeroi gaaynggal cohort, which began study visits during pregnancy ^{Reference Ashman, Collins and Weatherall14} , highlighted that Aboriginal and Torres Strait Islander mothers were more likely to begin their pregnancies with higher rates of obesity than is recommended for pregnancy which has long term implications for child health. In particular, children born from overweight and obese mothers from this cohort developed early childhood obesity ^{Reference Pringle, Weatherall and Roberts20} . Additionally, the infants born to obese mothers were identified to have kidneys that were disproportionally small leaving these infants at risk for future kidney disease ^{Reference Lee, Lumbers and Oldmeadow17} . Understanding why Indigenous families are at risk of poor kidney health was an important priority for this Indigenous community and was included within the study design for this reason ^{Reference Rae, Weatherall, Blackwell, Pringle, Smith and Lumbers21} . While these results can be distressing for communities to hear, they are important to help establish appropriate times in the life course for the initiation of health programmes and services. Evidence suggests that growing rates of maternal obesity and perinatal interventions need to be developed in both the pre-conception as well as inter-conception periods to support mothers in maintaining healthy body weight during these critical years.

Birth outcomes for the Gomeroi gaaynggal cohort demonstrate that changes in maternity care for Indigenous women are desperately needed to reduce preterm birth rates and improve birth weights at both ends of the birth weight spectrum (small-for-gestational age and large-for-gestational age) ^{Reference Pringle, Lee and Weatherall25} . Infants born large for gestational age were more likely to have mothers with obesity, elevated glucose or a diagnosis of gestational diabetes. The research team of Gomeroi gaaynggal showed that mothers; delivering infants prematurely (<37 weeks) were highly likely to have renal dysfunction with elevated protein: creatinine and albumin: creatinine during their pregnancy ^{Reference Lee, Collins and Schumacher18–Reference Pringle, Weatherall and Roberts20} . While women with gestational hypertension were more likely to have elevated glucose and high body fat, and those with gestational diabetes will have both elevated glucose and elevated protein: creatinine and albumin: creatinine.

This work highlights that Closing the Gap in poor perinatal outcomes requires more than the standard model of care in pregnancy to support and identify health needs of Indigenous women. While assessment of gestational diabetes and gestational hypertension are standard components of clinical care in pregnancy, screening for renal function is not, suggesting that early pregnancy screening of renal function may assist in reducing preterm birth risk factors ^{Reference Pringle, Weatherall and Roberts20} . These previous studies have taken place over a wide range of time (e.g., for 20+ years) however some of this earlier data continues to be relevant in contemporary contexts, and especially the perinatal chronic disease markers and health service utilisation data where available in some of the studies ^{Reference Comino, Craig and Harris12,Reference Kemp, Grace and Comino13,Reference Maple-Brown, Lee and Longmore15,Reference Kildea, Gao and Hickey38} . It is important to note that the Closing the Gap Implementation Plan 2026 continues to outline targets aimed at improving maternal and infant health markers, including increasing the proportion of Indigenous babies with a healthy birth weight to 91% by 2031, and significant investment on Birthing on Country units across Australia; with renewed targets aiming to reach the desired positive outcomes for families and communities ³⁹ .

Other research teams around Australia have identified clinical approaches that are community-driven and can contribute to Closing the Gap in Aboriginal and Torres Strait Islander perinatal health. Work from the PANDORA cohort (now known as Diabetes in Pregnancy Partnership) in NT led by Professor Maple-Brown and colleagues ^{Reference Maple-Brown, Lee and Longmore15} are working to improve health systems during antepartum, postpartum and inter-pregnancy to ensure women have culturally safe and adequate care, education and follow-up screening. This is done through obstetric, midwifery and primary care to detect onset of pre-diabetes, gestational diabetes and the future risk of Type 2 diabetes ^{Reference Kirkham, Trap-Jensen and Boyle30} . The implementation of a Diabetes in Pregnancy Register in their geographic region resulted in an 80% increase in the reported prevalence of gestational diabetes for Aboriginal and Torres Strait Islanders, thus highlighting the critical need for primary and obstetric care that considers diabetes as a priority in this population; and to consider this earlier in pregnancy than traditional screening at 28 weeks gestation suggests ^{Reference Kirkham, Trap-Jensen and Boyle30} . The work of the Diabetes in Pregnancy and Gomeroi gaaynggal teams highlight the capacity of perinatal health to Close the Gap on future health outcomes and educational trajectories for Indigenous mothers and their children.

The perinatal period is an ideal time to work with women of all cultural backgrounds with other chronic health conditions which may provide risk to obstetric outcomes or those women who would benefit from additional support for post-delivery. During this time, women access pregnancy related care regularly, facilitating innovative approaches to health monitoring and education during their antenatal health visits. For example, mental health has been identified as an area of need by Mah et al. in her work with Aboriginal and Torres Strait Islander women and although, not associated with poorer outcomes in pregnancy it would likely be of benefit when all women are at risk of postpartum depression following delivery ^{Reference Mah, Pringle and Weatherall32,Reference Mah, Weatherall and Burrows40} . Recent study findings have highlighted that Indigenous women delivering through the Mater Mothers Hospital have high rates of asthma in pregnancy (23% compared to 12–16%) ^{Reference Clifton, Das, Flenady and Rae41,42} , which is a well-established risk for poor perinatal outcomes. Conservative estimates attribute maternal asthma to absolute increases of >1200 preterm births, >2800 neonatal hospitalisations and >1100 cases of low birth weight each year ^{Reference Murphy, Namazy and Powell43} . This preliminary work highlights a further health need would benefit from integration into current antenatal care during the perinatal period that should be considered for Aboriginal and Torres Strait Islander women.

Important work by Professors Kildea, Roe and their team have highlighted that Indigenous-led models of care can be incorporated into a tertiary maternity setting successfully (Mater Mothers Hospital, Brisbane) ^{Reference Kildea, Gao and Hickey38} . When undertaken with strong collaborative Indigenous-led governance and commitment by the tertiary setting alongside the community-controlled sector, the birthing outcomes can be improved for Aboriginal and Torres Strait Islander women ^{Reference Kildea, Gao and Hickey38} Results of this study has conclusively shown that innovative models of care effectively reduce the likelihood of preterm delivery (OR 0.53, 95% CI 0.37–0.76), increase likelihood for >5 antenatal visits (OR 1.82, 95% CI 1.29–2.58) and increase likelihood of exclusive breastfeeding upon discharge (OR 1.38, 95% CI 1.06–1.79) for Aboriginal and Torres Strait Islander women ^{Reference Kildea, Gao and Hickey38} . As a multi-agency model of care, known as the Birthing in Our Community (BiOC) programme ^{Reference Kildea, Gao and Hickey38} , this maternity service has Indigenous governance, continuity of midwifery care across the perinatal period, an increased number of Indigenous workers and perinatal care which is embedded within a wrap-around holistic approach with a focus on strengths-based approaches to family health and wellbeing ^{Reference Kildea, Gao and Hickey38,Reference Kildea, Hickey and Nelson44} . Like the work of the Aboriginal Birth Cohort, PANDORA, Gomeroi gaaynggal study and others, BiOC also shows that the service is being accessed by women with co-morbidities that include conditions such as autoimmune disorders, liver disease, heart disease and thyroid disease during their perinatal period ^{Reference Kildea, Gao and Hickey38} .