Lifestyle and sociodemographic risk factors for stillbirth by region of residence in South Australia: a retrospective cohort study

Lifestyle and sociodemographic risk factors for stillbirth by region of residence in South Australia: a retrospective cohort study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Lifestyle and sociodemographic risk factors for stillbirth by region of residence in South Australia: a retrospective cohort study Anneka Bowman, Thomas Sullivan, Maria Makrides, Vicki Flenady, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4096693/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Background Stillbirth rates remain a global priority and in Australia, progress has been slow. Risk factors of stillbirth are unique in Australia due to large areas of remoteness, and limited resource availability affecting the ability to identify areas of need and prevalence of factors associated with stillbirth. This retrospective cohort study describes lifestyle and sociodemographic factors associated with stillbirth in South Australia (SA), between 1998 and 2016. Methods All restigered births in SA between 1998 ad 2016 are included. The primary outcome was stillbirth (birth with no signs of life ≥ 20 weeks gestation or ≥ 400 grams if gestational age was not reported). Associations between stillbirth and lifestyle and sociodemographic factors were evaluated using multivariable logistic regression and described using adjusted odds ratios (aORs). Results A total of 363,959 births were included. Inadequate antenatal care access (assessed against the Australian Pregnancy Care Guidelines) was associated with the highest odds of stillbirth (aOR 3.93, 95% confidence interval (CI) 3.41–4.52). Other factors with important associations with stillbirth were plant/machine operation (aOR, 1.99; 95% CI, 1.16–2.45), birthing person age ≥ 40 years (aOR, 1.92; 95% CI, 1.50–2.45), paternal pensioner status (aOR, 1.83; 95% CI, 1.12–2.99), Asian country of birth (aOR, 1.58; 95% CI, 1.19–2.10) and Aboriginal/Torres Strait Islander status (aOR, 1.50; 95% CI, 1.20–1.88). The odds of stillbirth were increased in regional/remote areas in association with inadequate antenatal care (aOR, 4.64; 95% CI, 2.98–7.23), birthing age 35–40 years (aOR, 1.92; 95% CI, 1.02–3.64), Aboriginal and/or Torres Strait Islander status (aOR, 1.90; 95% CI, 1.12–3.21), paternal occupations: tradesperson (aOR, 1.69; 95% CI, 1.17–6.16) and unemployment (aOR, 4.06; 95% CI, 1.41–11.73). Conclusion Factors identified as independently associated with stillbirth odds include factors that could be addressed through timely access to adequate antenatal care and are likely relevant throughout Australia. The identified factors should be the target of stillbirth prevention strategies/efforts. The stillbirth rate in Australia is a national concern. Reducing preventable stillbirths remains a global priority. stillbirth perinatal death environment pregnancy reproductive health risk Background Globally, more than 2.64 million babies are stillborn annually, with the highest rates occurring in low- and middle-income countries (LMICs) ( 1 , 2 ). In high-income countries (HICs), preventable stillbirths continue to be of concern, with slow progress towards global targets for rate reduction. To address this issue, the Australian government appointed a Senate Select Committee on Stillbirth Research and Education in 2018 ( 3 ). Their report revealed that Australia had ‘slipped’ in its progress to reduce stillbirth rates in line with targets compared with other HICs. It also demonstrated that babies born to mothers living remotely were more likely to be stillborn than babies born in major cities ( 4 ). In 2020, Women and Birth published a series focused on stillbirth in Australia and identified the national action required to decrease rates ( 5 – 9 ). Rumbold et al. ( 9 ) highlighted the impact of inequity on stillbirth rates within select Australian populations, noting particular concern within communities experiencing isolation and socioeconomic disadvantage ( 9 ). Numerous risk factors in disadvantaged communities contribute to the widening gap in health inequality, further hindering stillbirth prevention ( 10 ). This research aims to identify lifestyle and sociodemographic risk factors for stillbirth in South Australia (SA) geographically and to explore these risks according to remoteness. Methods Study design and setting This was a retrospective state-wide observational cohort study using the SA perinatal outcomes dataset, including all births from 1998 to 2016 (cohort one). The dataset contains pregnancy outcomes categorised as live birth or stillbirth. The data were obtained anonymously, with all identifying fields removed prior to their provision for research purposes. The study concept, acceptability, methods and interim analysis were presented, reviewed, and approved by the NHMRC Centre for Research Excellence in Stillbirth Indigenous Advisory Committee at two separate timepoints. The final manuscript was reviewed and approved by local SA Indigenous researchers and senior health care advisors prior to submission. Materials In SA, all births are reported by midwives, birth attendants and obstetricians in standardised supplementary birth records. The SA Perinatal Outcomes Unit integrates continuous validation of the dataset by comparing data collected from the supplementary birth records to electronic hospital records at the time of coding. Sociodemographic characteristics and pregnancy and birth outcome data were recorded. Due to the later introduction of BMI to the data collection, analyses involving BMI were restricted to the years 2007–2016 (cohort two). Terminations of pregnancy were excluded. Definitions and Outcomes Variable definitions and time periods are provided in Table 1 . Information for all births (live or stillborn) ≥ 20 weeks gestational age (GA) of ≥ 400 grams at birth are reported. The primary outcome, stillbirth, was defined in line with the standard Australian Institute of Health and Wellbeing definition as the birth of a baby showing no signs of life at ≥ 20 weeks’ completed GA, or ≥ 400 grams birthweight where no GA is provided. Table 1 Study variables included, timepoint of collection and definition of each variable Variable (availability) Time point of collection Definition/Categorisation Study Variables Maternal ethnicity (1998–2016) First antenatal visit (booking visit) Self-reported Caucasian, Aboriginal, Torres Strait Islander, Aboriginal and Torres Strait Islander or Asian status. Aboriginal and/or Torres Strait Islander status includes identification by Aboriginal or Torres Strait Islander descent, self-identification of community acceptance of Aboriginal and/or TSI status. Births to women recorded as Aboriginal, Torres Strait Islander, and/or Aboriginal were categorised as Aboriginal and/or Torres Strait Islander women for analysis. Women recorded as Asian were categorised as Asian, and women recorded as Caucasian were categorised as Caucasian. Country of birth (1998–2016) First antenatal visit (booking visit) Australia, Oceania, Europe/USSR, Middle East/Nth Africa, SE Asia, NE Asia, Southern Asia, Nth America, South/Central America, Africa as reported by women. Statistical areas Level 3 (SA3) areas (1998–2016) At birth Place of usual residence data. Australia Bureau of Statistics modified Accessibility and Remoteness Index of Australia (ARIA+) score average for each SA3 area compiled from SA2 area ARIA + scores. SA3 area was assigned on maternal usual place of residence at birth. Areas were classified as; major cities (geographic distance imposes minimal restrictions upon accessibility to the widest range of goods, services and opportunities for social interaction), inner regional areas (geographic distance imposes some restrictions upon accessibility to the widest range of goods, services and opportunities for social interaction), outer regional areas (geographic distance imposes a moderate restriction upon accessibility to the widest range of goods, services and opportunities for social interaction), remote/very remote areas (geographic distance imposes the highest restriction upon accessibility to the widest range of goods, services and opportunities for social interaction). Map of South Australia areas according to the ABS modified ARIA + score with superimposed SA3 boundaries shown below (Fig. 1). Adequacy of antenatal care access (1998–2016) At birth Adequacy of antenatal care was assessed per pregnancy according to the Australian Clinical Practice Guidelines: Pregnancy Care that recommends nulliparous women have a minimum of 10 antenatal visits, and multiparous women; a minimum of 7 antenatal visits (40). Adequacy was assigned separately by parity (nulliparous and multiparous) stratified by gestational age. Maternal age (1998–2016) At birth Categories: 12–19 years, 20–24 years, 25–29 years, 30–34 years, 35–40 years, ≥ 40 years Marital status (1998–2016) At birth Categories: Married/Unmarried (encompasses; never married, widowed, divorced, separated) Smoking status (1998–2016) First antenatal visit (booking visit) and again at 20 weeks GA Non-smokers as self-reported smoking status at booking visit and 20 weeks GA. Women were classified as smokers if any smoking was reported at either visit. Parity (1998–2016) First antenatal visit (booking visit) Nulliparous, multiparous Chronic health medical conditions At birth Previous diabetes or chronic hypertension Parental occupation Father’s occupation at birth, mother occupation prior to and/or during pregnancy before ‘home duties’. One of 13 occupation groups according to the ABS Australia Standard Classification of Occupations (ASCO) first edition Inter-pregnancy interval Calculated as the number of months between the previously recorded birth, and date of conception of the current pregnancy (> 6 months, < 6 months). Maternal BMI (2007–2016) First antenatal visit (booking visit) measurements Calculated as weight in kgs divided by height (in meters) squared. Underweight (< 19), healthy ( 19 – 24 ), overweight ( 25 – 29 ) and class 1 obesity (30–34 years), class 2 obesity (35–39 years), morbid obesity (40+) Anaemia At any stage during pregnancy Anaemia diagnosed as maternal Hb 41 completed weeks GA) Prolonged labour At birth Labour duration of > 18 hrs Past obstetric history At birth Previous caesarean section, previous stillbirth. Medical conditions At birth Asthma during pregnancy, urinary tract infection during pregnancy Babies born small for gestational age After birth SGA; below the 10th percentile were determined using Australian national birthweight percentiles estimated from a large Australian cohort of infants born between 1997 and 2007 (41). Rural and remote living at birth status was based on statistical areas level 3 (SA3) data associated with each birth. Australia Bureau of Statistics modified Accessibility and Remoteness Index of Australia (ARIA+) score average for each SA3 area compiled from SA2 area ARIA + scores. The areas were classified as: major cities, inner regional areas, outer regional areas, or remote/very remote areas. When exposure data or variable data were missing, individual births were excluded from the analysis. [Insert Table 1 here] Statistical analysis Variables were categorised as outlined in Table 1 . Categories with < 10 stillbirths per group were reported as ‘< 10’, and crude odds ratios (ORs) concealed. Within multivariable analysis where categories had fewer than five stillbirths, analyses are reported as ‘< 5’. Logistic regression was performed using the statistical software STATA 16 IC ( 11 ) to determine associations between potential risk factors and stillbirth, described using odds ratios (ORs) and 95% confidence intervals (95% CIs). Unadjusted and adjusted models were considered, with adjustments made for variables that demonstrated significance during univariate analysis (p < 0.001). For each risk factor, adjustment variables included year of birth, adequate antenatal care (ANC) access (adjusted for GA at birth), marital status, ethnicity, smoking status, parity, remote/rural status, age, previous stillbirth, medical conditions (preexisting diabetes, hypertension, anaemia), plurality, interpregnancy interval, insurance status, and obstetric complications (gestational diabetes, gestational hypertension, antepartum haemorrhage [APH]). The cohort was stratified by residential remoteness, and the analysis was repeated using the same adjustment variables (excluding rural/remote status). Factors demonstrating the strongest association with stillbirth odds were further explored to calculate SA-specific population attributable fractions ( 12 ) and annual attributable stillbirths per factor (n). The analysis was repeated for cohort two, which was additionally adjusted for BMI (Tables 4 and 5 ). Table 4 Multivariable analysis of risk factors and their association with stillbirth odds in SA, between 2007 and 2016 (cohort two). Variables Adjusted OR Smoking Non-smoker Referent Smoker 1.16 (0.95, 1.42) Insurance type Private Referent Public 0.82 (0.65, 1.03) Marital Status Married Referent Unmarried 1.23 (0.97, 1.55) Adequate ANC access Adequate antenatal care access Referent Inadequate antenatal care access 4.02 (3.19, 5.06) Maternal age 12–19 years 1.20 (0.81, 1.78) 20–24 years 0.98 (0.76, 1.27) 25–29 years Referent 30–34 years 1.07 (0.96, 1.32) 35–39 years 1.17 (0.90, 1.51) ≥ 40 years 2.00 (1.40, 2.86) Maternal occupation Professionals/Managers/Admin Referent Clerks/Sales people 1.02 (0.81, 1.29) Tradespersons/Labourers/Lab & machine operators 1.08 (0.75, 1.56) Student 1.45 (0.97, 2.17) Unemployed/Pensioner/Home duties 1.19 (0.93, 1.53) Paternal occupation Professionals/Managers/Admin Referent Clerks/Salespeople 1.02 (0.73, 1.43) Tradespersons/Labourers/Lab & machine operators 1.10 (0.89, 1.36) Student 1.13 (0.66, 1.93) Unemployed/Pensioner/Home duties 1.46 (1.04, 2.07) Interpregnancy interval > 6 months Referent ≤ 6 months 1.21 (0.90, 1.62) Country of birth* Australia Referent Europe/USSR 1.14 (0.80, 1.63) Middle east/Nth Africa 1.87 (1.23, 2.83) SE Asia 0.93 (0.62, 1.40) NE Asia 0.90 (0.54, 1.50) Southern Asia 1.67 (1.24, 2.24) Nth America < 5 SBs South/Central America < 5 SBs Africa 1.96 (1.30, 2.97) Oceania < 5 SBs Ethnicity Caucasian Referent Aboriginal/Torres Strait Islander 1.17 (0.80, 1.72) Asian 1.43 (1.13, 1.82) Parity Nulliparous 0.80 (0.65, 1.00) Multiparous Referent Remoteness Major City Referent Inner regional area 1.08 (0.83, 1.40) Outer regional area 1.30 (0.97, 1.75) Remote/Very remote area 1.36 (0.96, 1.91) Anaemia No anaemia during pregnancy Referent Anaemia during pregnancy 1.17 (0.91, 1.52) aOR adjusted for year of birth, adequate ANC access, marital status, maternal BMI, maternal ethnicity, smoking status, parity, remote/rural status, maternal age, previous stillbirth, medical conditions (pre-existing diabetes or hypertension, anaemia), plurality, interpregnancy interval, insurance status, obstetric complications (gestational diabetes, gestational hypertension, APH) *maternal ethnicity excluded from model of adjustment Table 5 Multivariable analysis of risk factors and their association with stillbirth odds in SA, between 2007 and 2016, stratified by areas of remoteness (cohort two). Maternal BMI category Total Births Stillbirth rate/1000 births Crude OR (95% CI) Adjusted OR for risk factors of stillbirth* Adjusted OR for risk factors of stillbirth stratified by region of residence** Major city† Inner regional† Outer regional† Remote/very remote† Underweight (< 19) 5,421 3.49 0.80 (0.50, 1.27) 0.72 (0.44, 1.19) 0.66 (0.08, 5.17) Referent Referent Referent Healthy weight ( 19 – 24 ) 67,664 4.37 Referent Referent Referent Overweight ( 25 – 29 ) 45,594 4.32 0.99 (0.82, 1.19) 1.02 (0.84, 1.24) 1.44 (0.82, 2.54) 0.96 (0.76, 1.20) 1.23 (0.60, 2.52) 1.10 (0.54, 2.26) Obese class 1 ( 30 – 34 ) 22,518 4.38 1.15 (0.96, 1.38) 1.06 (0.82, 1.36) 1.06 (0.50, 2.23) 1.33 (1.05, 1.68) 1.39 (0.67, 2.86) 0.69 (0.28, 1.70) Obese class 2 (35–39) 10,426 6.01 1.38 (1.04, 1.83) 1.48 (1.08, 2.02) 1.24 (0.49, 3.12) Morbidly Obese (40+) 6,750 5.60 1.28 (0.91, 1.08) 1.29 (0.89, 1.87) 0.99 (0.34, 2.92) Missing 42,228 4.83 NA NA NA NA NA NA * aOR adjusted for year of birth, adequate ANC access, marital status, rural/remote status, maternal ethnicity, smoking status, parity, maternal age ( 40), previous stillbirth, medical conditions (pre-existing diabetes or hypertension, anaemia), plurality, interpregnancy interval, insurance status, obstetric complications (gestational diabetes, gestational hypertension, APH) ** aOR adjusted for year, adequate ANC access, marital status, smoking status, parity, maternal age, previous stillbirth, medical conditions (pre-existing diabetes or hypertension, anaemia), plurality, interpregnancy interval, insurance status, obstetric complications (gestational diabetes, gestational hypertension, APH) †stratified analysis conducted using populations designated as living within a major city (n = 110,075 (407 stillbirths)), Inner regional area (n = 19,569 (73 stillbirths)), outer regional area (n = 11,363 (51 stillbirths), or remote/very remote area (n = 7795 (40 stillbirths)). Due to cohort size, BMI categories were grouped (healthy (BMI 30)). Results Data were available for 363,933 births in SA including 1767 stillborn babies following exclusions (Table 2 ). Birthing people were predominantly Australian born (81%) with 86% of Australian born people identifying as Caucasian. The majority (71%) lived in major cities, followed by inner regional areas (14%), outer regional areas (8%) and remote or very remote areas (6%). During pregnancy, 13.5% of birthing people access less than the recommended number of ANC visits (Australian Clinical Practice Guidelines: Pregnancy Care recommends that nulliparous women have a minimum of 10 and multiparous women have a minimum of 7). Most birthing people were nonsmokers (78%) and gave birth in the Australian public health care system (70%) (Table 2 ). Cohort two included 201,315 births (918 stillborn babies) between 2007 and 2016. [Insert Table 2 here] The stillbirth rate in SA over the study period was 4.85/1000 births. Stillbirth rates were highest for birthing people who had inadequate ANC access (13.78/1000 births) and those who reported that they (8.78/1000 births) or their partner were a ‘pensioner’ (10.21/1000 births). Stillbirths were high among ‘unemployed’ individuals and ‘plant or machine operators’ (8.15 and 7.97/1000 births, respectively), those aged less than 19 or over 40 (7.51 and 7.71/1000 births, respectively), and those who were unmarried (7.63/1000 births) or smoked (6.20/1000 births). Stratification by remoteness status suggested that rates of stillbirth differed minimally by remoteness classification (Table 3 ). Adequacy of antenatal care access (ANC) Crude analysis demonstrated a fourfold increase in stillbirth odds for birthing people who received inadequate ANC compared with those who received adequate ANC (Table 2 ). This increased odds of stillbirth with inadequate ANC access was observed across all areas of residence (Table 3 ). Adjusted analysis demonstrated that birthing people in SA who experienced inadequate versus adequate ANC access had fivefold greater odds of stillbirth (inner region: aOR 5.56; 95% CI 3.91–7.92; remote/very remote region: aOR 4.64; 95% CI 2.98–7.23). Parental occupation Crude analysis indicated that several occupations were associated with stillbirth. Through multivariable analysis, birthing people who worked as plant/machine operators had almost double the odds of stillbirth versus professionals (aOR 1.99; 95% CI 1.16–3.43). Compared with professionals, unemployed birthing people also had increased odds of stillbirth (aOR 1.34; 95% CI 1.01–1.79). No clear differences were noted in the area stratified analysis considering unemployment (compared with major cities, outer regional areas: aOR 1.59; 95% CI 0.63–4.03, remote/very remote areas: aOR 1.35; 95% CI 0.54–3.39). Unemployed nonbirthing parent status (aOR 1.33; 95% CI 1.01–1.76) and pensioner status (aOR 1.83; 95% CI 1.12–2.99) versus professional status were associated with increased odds of stillbirth. Non-birthing parent tradeperson status (aOR 1.69; 95% CI 1.17–6.16) and unemployment (aOR 4.06; 95% CI 1.41–11.73) was independently associated with stillbirth within remote/very remote areas of SA (Table 3 ). Birthing persons’ country of birth Crude analysis demonstrated increased odds of stillbirth for birthing people born in Southern Asia, the Middle East/North Africa, and Africa versus Australia (Table 2 ). Increased odds of stillbirth were shown for birthing people from Southern Asia (versus Australia) (aOR 1.58; 95% CI 1.19–2.10). This was mirrored for South Asian-born birthing people residing in major cities (Table 3 ). Crude analysis revealed greater stillbirth odds for birthing people born in Middle Eastern/North African countries; however, this increase was attenuated in multivariable analyses. Similar results were shown for birthing people from African countries (64% increased odds of stillbirth) (versus Australia); however, the odds were attenuated in the multivariate analysis (aOR 0.82; 95% CI 0.29–2.27). The odds of stillbirth did not increase for any of the other countries in which the birthing people were born compared with those for which the birthing people were born in Australia. Birthing persons’ ethnicity Aboriginal and/or Torres Strait Islander status (versus Caucasian status) was shown to increase stillbirth odds through crude and adjusted analyses (cOR 2.55; 95% CI 2.11–3.08, and aOR 1.50; 95% CI 1.20–1.88). Stratification by place of residence revealed that the odds of stillbirth for Aboriginal and/or Torres Strait Islander versus Caucasian people were almost double within inner regional (aOR 1.91; 95% CI 1.06–3.46) and remote/very remote areas (aOR 1.90; 95% CI 1.12–3.21). Self-reported Asian ethnicity (versus Caucasian status) did not show an increase in stillbirth odds (aOR 1.12; 95% CI 0.93–1.35). Stratification by areas of remoteness could not be performed due to small case numbers per subgroup. [Insert Table 3 here] BMI (cohort two) Similar to cohort one, analyses of cohort two demonstrated increased odds of stillbirth with inadequate ANC access, particular parental occupations, and certain birthing person’s country of birth and ethnicity (Table 4 ). Birthing person BMI was associated with marginally increased odds of stillbirth for BMI’s between 35 and 39 at the first antenatal appointment (Table 5 ). These findings were mirrored through remoteness stratification analysis. The odds of stillbirth were not significant for morbidly obese birthing people according to the analysis, possibly reflecting an underpowered sample size in this category. Through models adjusted for BMI, the associations between Aboriginal and/or Torres Strait Islander ethnicity and stillbirth odds decreased, eliminating this factor’s independent association with stillbirth. [Insert Tables 4 and 5 here] Population Attributable Fractions (PAFs) (Table 6 ) Table 6 Multivariable analysis for select risk factors for birthing people residing in South Australia between 1998 and 2016, the population attributable fractions (PAF), and attributable stillbirths* (cohort one) Variables aOR (95% CI) PAF (%)** Total preventable SB for study period (1998–2016) (births) Average preventable SB per year in SA (births) Smoking status Non-smoker Referent .. .. Smoker 1.13 (0.99, 1.28) 3.31% 52 3 Adequate ANC access Adequate ANC access Referent .. .. Inadequate ANC access 3.93 (3.41, 4.52) 27.65% 437 24 Maternal age ≤ 35 years Referent .. .. > 35 years 1.40 (1.23, 1.60) 6.32% 100 6 Maternal Occupation All other occupations Referent .. .. Plant or machine operators 1.74 (1.04, 2.91) 0.40% 6 0.3 Maternal country of birth All other countries (excluding only population of interest below) Referent .. .. Southern Asian countries 1.64 (1.23, 2.18) 1.33% 21 1 African countries 1.55 (1.21, 1.99) 1.52% 24 1 Remoteness Major city/Inner regional Referent .. .. Outer regional/remote/very remote 1.23 (1.08, 1.41) 3.24% 51 3 *SB = stillbirths, Remoteness = remoteness classification of the maternal residential postcode at the time of birth, aOR = adjusted odds ratio, odds adjusted for year of birth, adequate ANC access, marital status, smoking status, parity, remoteness, maternal age, maternal pre-existing medical conditions (diabetes, hypertension, anaemia), insurance status, interpregnancy interval, plurality, gestational diabetes or hypertension, antepartum haemorrhage (adjustments of individual factors exclude the factor of interest within adjustment). **PAF calculated using methods described by Mansournia et al ( 13 ) Factors with the strongest independent associations with stillbirth odds were selected to determine PAFs (Table 6 ). The PAF enabled examination of the direct percentage of stillbirths attributed to each risk factor within the population according to the populational prevalence. The factors with the greatest impacts on stillbirth rates in SA were inadequate ANC access (PAF: 27.65%) and birthing person age > 35 years (PAF: 6.32%). The PAFs for smoking and age > 35 years were 3.31% and 6.32%, respectively. [Insert Table 6 ] Adequate ANC access in Australia has been highlighted as a marker of inequity between areas of remoteness and major cities ( 3 ) and is well established as the best means to ensure a healthy pregnancy and effective preventative care for poor pregnancy outcomes. Our results suggest that inadequate ANC access (as per the Australian pregnancy care guidelines ( 13 )) is strongly associated with increased odds of stillbirth. The recommended number of ANC visits is 10 for first pregnancies and seven for subsequent uncomplicated pregnancies ( 13 ). PAF calculations indicated that if all recommended appointments were accessible to all birthing people, 437 stillbirths could have been prevented over this study period, equating to an average of 24 stillbirths per year. Previous research examining the impact of ANC on stillbirths has revealed a U-shaped curve and has suggested that 14 visits is optimal to minimise risk ( 14 ). Globally, there are notable variations in the minimum number of visits recommended; German studies suggest 12 ( 15 ), USA, 11 ( 16 ), and Canada ( 17 , 18 ). Strategies to encourage improved ANC access, such as culturally safe care models, and addressing travel and financial barriers to access, alongside further consideration of an increase in the minimum number of recommended ANC visits in Australia, should constitute part of stillbirth prevention efforts. Remote and rural status has previously been shown to have an independent association with intrapartum stillbirth in remote Western Australia due to a lack of access to high-level care during labour, although Aboriginal and/or Torres Strait Islander women were excluded from these findings because the main outcome focused on migrant women in Western Australia ( 19 ). Comparable results have been shown in studies examining the impact of regional and remote living on stillbirth rates in Australia ( 20 , 21 ), although the findings were limited by cohort size and limited confounder adjustment. Our analysis revealed marginally greater odds of stillbirth within regional areas (i.e., the outer and inner regional areas), and for birthing people who smoked during pregnancy, who were unmarried or of advanced age (over 35 years). Aboriginal and/or Torres Strait Islander birthing people were at increased risk of stillbirth in inner and outer regional areas. These findings further highlight the need for increased preventative care for those living in regional and remote areas. There are mixed findings regarding the association between Aboriginal and/or Torres Strait Islander People and stillbirth odds. Some have reported increased odds of stillbirth, while others have reported equivalence ( 22 , 23 ). Our study suggested that Aboriginal and/or Torres Strait Islander birthing people are at risk of 21 stillbirths per year in SA. Compared with Caucasian birthing people, Aboriginal and/or Torres Strait Islander birthing people residing in inner regional and remote/very remote areas experience greater stillbirth odds than their city-dwelling counterparts. An analysis incorporating BMI into models of adjustment diminished this association, indicating that there was no independent association with stillbirth odds and that strategies to address BMI may be key. This may implicate a combined lack of culturally safe care models, limited birthing on country services, and poorly resourced ANC in regional and remote areas of SA. Cultural safety and birthing on country training of health care professionals has been shown to improve access for Aboriginal and/or Torres Strait Islander families, including trauma-informed care ( 24 ). South Asian ethnicity has previously been shown to have an independent association with stillbirth odds in HIC populations globally ( 19 , 25 – 30 ). Analyses of stillbirth odds for birthing people of South Asian ethnicity have differed when country of birth has been used as a proxy for ethnicity ( 19 , 22 , 26 – 28 , 31 ) versus when self-reported ethnicity has been used ( 25 , 29 , 30 ). Although country of birth is a commonly used proxy for ethnicity, there is potential for misclassification. The findings of this study demonstrate that South Asian (versus Australian) countries of birth are associated with stronger odds of stillbirth than self-reported Asian (versus Caucasian) ethnicity. Country of birth should be considered an independent factor when assessing the risk of stillbirth at the individual level. Certain occupations and their associated exposures to chemicals or lifting and rotating shift work have previously been implicated as contributors to stillbirth in HICs ( 32 – 34 ). To our knowledge, there has been no prior research examining associations between stillbirth and occupational groups within an entire population. The increased odds of stillbirth for plant- or machine-operating birthing people warrants attention. As does paternal unemployment and tradesperson status in remote and very remote areas. – both also associated with increased stillbirth odds in SA. According to previous research on HICs, obesity consistently and independently increases stillbirth odds ( 31 , 35 , 36 ). Our findings demonstrated that a BMI between 35 and 39 was associated with increased odds of stillbirth, but this was not observed when the BMI reached ≥ 40. This observation may be due to the low number of birthing people with a BMI ≥ 40, rendering the analysis underpowered. However, the absence of increased stillbirth odds for birthing people with a BMI ≥ 40 could be due to the different care pathways and tailored care and monitoring for this group. In SA, at their first antenatal appointment, this group is provided specific ANC programs focused on pregnancy risks and complications associated with morbid obesity ( 37 ). Strengths and Limitations The strengths of this study lie in the comprehensive and detailed measures for each birth, including the inclusion of parental occupational coding and ethnicity alongside country of birth. Factors included within this dataset are collected routinely for the entire study period without changes in the definition or classification of diseases. Due to the large number of stillbirths included in this study, analysis of many factors was possible, allowing meaningful and generalisable results. However, we acknowledge several limitations. The omission of BMI data collected prior to 2007 prevented the analysis of BMI across the study period. Cohort two encompasses BMI, but due to the smaller cohort size, comprehensive analysis was not possible. This study has the same limitations ubiquitous to research examining routinely collected perinatal data, which may not have been intended solely for research purposes. The lack of data concerning domestic assault, pollution, consanguinity, sleep position and drug/alcohol use leaves potential for residual bias due to unmeasured covariates. The current analysis does not account for the temporal changes in individual factors’ impacts over the course of the study period. The use of average ARIA + scores from SA2’s encompassed within each SA3 for remoteness status has the potential to result in misclassification of remoteness status for some populations within assigned categories. Conclusion This research presents a robust and comprehensive analysis of a large SA cohort spanning almost two decades. Our findings highlight gaps in national- and state/territory-level analysis of stillbirth. By omitting stratification by remoteness, previous research has masked disparities between marginalised groups within regions that are shown to have the highest rates of stillbirth. Although this disparity has been well established and highlighted as a focus of addressing preventable stillbirth, further research stratified by remoteness is needed. It is clear from our findings that the stillbirth odds for birthing people aged 35–40 years or with specific occupations differ according to remoteness classification, although smaller populations living in regional and remote areas render our analysis underpowered for some factors. Through robust subanalysis incorporating comprehensive multivariable adjustment (including BMI), our findings demonstrate that birthing person Aboriginal and/or Torres Strait Islander status is not independently associated with stillbirth, and while there is no independent association, holistic and culturally safe care is essential. Improved access to care will aid in addressing factors that may be independently associated with and contributing to stillbirth rates within this population. Efforts are required to ensure that birthing people have adequate ANC access, and this may require review through national care guidelines. Although current pregnancy care guidelines and policies are rigorous and based on evidence at the national level, areas of ambiguity and differences exist for health care providers in regional and remote areas, which are overlaid with finite access to resources. Our findings indicate that adequate ANC access is the greatest risk factor for stillbirth in remote SA. Complexities preventing engagement in care and poor attendance may reflect access to and acceptability of ANC programs across all facets of society. Limitations of national policy and guidelines for ANC access in regional and remote areas result in care that is complex to deliver within limited resource settings, often with limited accessibility. The evidence presented indicates that further research is needed to determine the required minimum number of ANC visits and to suggest a focus on providing adequate access to the recommended number of ANC visits for all birthing people. This also needs to take into consideration the implications for current health care systems, especially in remote and regional areas. Declarations Ethics approval and consent to participate Ethical approval was granted from the SA Department of Health and Wellbeing Committee (ID HREC19SAH13) on 11 th of June 2019, and the Aboriginal Health Council of SA Human Research Ethics Committee (ID 04-19-816) on the 8 th of May 2019. Participant consent was not an ethical requirement for this research. Consent for publication not applicable Availability of data and materials The deidentified data analysed are not publicly available, but requests to the corresponding author for the data will be considered on a case-by-case basis in discussion with the South Australian Data Custodian. Requests may be referred to the South Australian Data Custodian to obtain approval. Competing interests The authors declare that they have no competing interests. Funding No funding was received for this research outside of the primary authors affiliated organisations. Funding was granted for this project in the form of research training stipends (University of Adelaide) and PhD top-up scholarships (Stillbirth Centre of Research Excellence) for A Bowman during the course of their higher degree by research. Author contributions AB: Conceptualisation, Data curation, Formal Analysis, Funding acquisition, Project administration, Software, Methodology, Writing – original draft, Interpretation of data TS: Formal Analysis, Methodology, Supervision, Validation, Writing – review and editing VF: Conceptualisation, Methodology, Supervision, Writing – review and editing, Analysis and interpretation of data MM: Conceptualisation, Data curation, Resources, Software, Supervision, Writing – review and editing ES: Writing – review and editing, Methodology, Interpretation of the data CL: Writing – review and editing, Analysis and interpretation of data DSB: Conceptualisation, Supervision, Writing – review and editing, Analysis and interpretation of data KH: Supervision, Writing – review and editing, Analysis and interpretation of data PM: Conceptualisation, Methodology, Software, Supervision, Writing – original draft, Writing – review and editing, Analysis and interpretation of data Acknowledgments The authors would like to acknowledge and thank SAHMRI Women and Kids for their support through this project, and also the Stillbirth Centre of Research Excellence for their financial support during the project. The University of Adelaide is also acknowledged for their financial support of the primary author during their higher degree by research of which this project forms a main component. Acknowledgement is also extended to the Stillbirth Centre of Research Excellence Indigenous Advisory Committee, and also the Aboriginal Communities and Families Health Research Alliance who assisted in guiding the objectives, and interpreting the results of this project. References Flenady V, Koopmans L, Middleton P, Froen JF, Smith GC, Gibbons K, et al. Major risk factors for stillbirth in high-income countries: a systematic review and meta-analysis. The Lancet. 2011;377(9774):1331-40. Frøen JF, Cacciatore J, McClure EM, Kuti O, Jokhio AH, Islam M, et al. Stillbirths: why they matter. The Lancet. 2011;377(9774):1353-66. Government. A. Response to: the Senate Select Committee on Stillbirth Research and Education Report. Canberra; 2019. Select Senate Committee on Stillbirth Research and Education. Select Committee on Stillbirth Research and Education Report: Stillbirth Research and Education. Parliment House, Canberra; 2018. Boyle FM, Horey D, Dean JH, Loughnan S, Ludski K, Mead J, et al. Stillbirth in Australia 5: Making respectful care after stillbirth a reality: The quest for parent-centred care. Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):531-6. Ellwood DA, Flenady VJ. Stillbirth in Australia 6: The future of stillbirth research and education. Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):537-9. Flenady VJ, Middleton P, Wallace EM, Morris J, Gordon A, Boyle FM, et al. Stillbirth in Australia 1: The road to now: Two decades of stillbirth research and advocacy in Australia. Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):506-13. Gordon A, Chan L, Andrews C, Ludski K, Mead J, Brezler L, et al. Stillbirth in Australia 4: Breaking the Silence: Amplifying Public Awareness of Stillbirth in Australia. Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):526-30. Rumbold AR, Yelland J, Stuart-Butler D, Forbes M, Due C, Boyle FM, et al. Stillbirth in Australia 3: Addressing stillbirth inequities in Australia: Steps towards a better future. Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):520-5. Fox H, Topp SM, Lindsay D, Callander E. Ethnic, socio-economic and geographic inequities in maternal health service coverage in Australia. The International Journal of Health Planning and Management. 2021;36(6):2182-98. StataCorp. Stata Statistical Software: Release 16. In: Station. C, editor. TX:: StataCorp LLC.; 2023. Mansournia MA, Altman DG. Population attributable fraction. British Medical Journal (Online). 2018;360:k757. Australian Government Department of Health. Clinical Practice Guidelines: Pregnancy Care. In: Australian Government Department of Health, editor. Canberra2020. Vintzileos AM, Ananth CV, Smulian JC, Scorza WE, Knuppel RA. Prenatal care and black-white fetal death disparity in the United States: Heterogeneity by high-risk conditions. Obstetrics and Gynecology. 2002;99(3):483-9. Reime B, Lindwedel U, Ertl KM, Jacob C, Schucking B, Wenzlaff P. Does underutilization of prenatal care explain the excess risk for stillbirth among women with migration background in Germany? Acta Obstetricia et Gynecologica Scandinavica. 2009;88(11):1276-83. Partridge S, Balayla J, Holcroft CA, Abenhaim HA. Inadequate Prenatal Care Utilization and Risks of Infant Mortality and Poor Birth Outcome: A Retrospective Analysis of 28,729,765 U.S. Deliveries over 8 Years. American Journal of Perinatology. 2012;29(10):787-93. Health Nexus Best Start Resource Centre. Ontario Prenatal Education 2022 [Available from: https://www.ontarioprenataleducation.ca/routine-prenatal-care/. Heaman MI, Martens PJ, Brownell MD, Chartier MJ, Derksen SA, Helewa ME. The Association of Inadequate and Intensive Prenatal Care With Maternal, Fetal, and Infant Outcomes: A Population-Based Study in Manitoba, Canada. J Obstet Gynaecol Can. 2019;41(7):947-59. Mozooni M, Pennell CE, Preen DB. Healthcare factors associated with the risk of antepartum and intrapartum stillbirth in migrants in Western Australia (2005-2013): A retrospective cohort study. PLoS Medicine. 2020;17(3):e1003061. Graham S, Pulver LRJ, Wang YA, Kelly PM, Laws PJ, Grayson N, et al. The urban-remote divide for Indigenous perinatal outcomes. Medical Journal of Australia. 2007;186(10):509-12. Robson S, Cameron CA, Roberts CL. Birth outcomes for teenage women in New South Wales, 1998-2003. Australian and New Zealand Journal of Obstetrics and Gynaecology. 2006;46(4):305-10. Gordon A, Raynes-Greenow C, McGeechan K, Morris J, Jeffery H. Risk factors for antepartum stillbirth and the influence of maternal age in New South Wales Australia: A population based study. BMC Pregnancy and Childbirth. 2013;13:12. Hodyl NA, Grzeskowiak LE, Stark MJ, Scheil W, Clifton VL. The impact of Aboriginal status, cigarette smoking and smoking cessation on perinatal outcomes in South Australia. Medical Journal of Australia. 2014;201(5):274-8. Kildea S, Hickey S, Barclay L, Kruske S, Nelson C, Sherwood J, et al. Implementing birthing on country services for Aboriginal and Torres Strait Islander families: RISE framework. Women and Birth. 2019;32(5):466-75. Balchin I, Whittaker JC, Patel R, Lamont RF, Steer PJ. Racial variation in the association between gestational age and perinatal mortality: Prospective study. British Medical Journal. 2007;334(7598):833-5. Berman Y, Ibiebele I, Patterson JA, Randall D, Ford JB, Nippita T, et al. Rates of stillbirth by maternal region of birth and gestational age in New South Wales, Australia 2004–2015. Australian and New Zealand Journal of Obstetrics and Gynaecology. 2020;60(3):425-32. Davies-Tuck ML, Davey MA, Wallace EM. Maternal region of birth and stillbirth in Victoria, Australia 2000-2011: A retrospective cohort study of Victorian perinatal data. PLoS ONE. 2017;12(6):e0178727. Drysdale H, Ranasinha S, Kendall A, Knight M, Wallace EM. Ethnicity and the risk of late-pregnancy stillbirth. Medical Journal of Australia. 2012;197(5):278-81. Heazell A, Li M, Budd J, Thompson J, Stacey T, Cronin RS, et al. Association between maternal sleep practices and late stillbirth - findings from a stillbirth case-control study. BJOG: An International Journal of Obstetrics and Gynaecology. 2018;125(2):254-62. Ravelli AC, Tromp M, Eskes M, Droog JC, van der Post JA, Jager KJ, et al. Ethnic differences in stillbirth and early neonatal mortality in The Netherlands. Journal of Epidemiology and Community Health. 2011;65(8):696-701. Gardosi J, Madurasinghe V, Williams M, Malik A, Francis A. Maternal and fetal risk factors for stillbirth: Population based study. British Medical Journal (Online). 2013;346(7893):f108. Bonde JP, Jørgensen KT, Bonzini M, Palmer KT. Miscarriage and occupational activity: A systematic review and meta-analysis regarding shift work, working hours, lifting, standing, and physical workload. Scandinavian Journal of Work, Environment and Health. 2013;39(4):325-34. Mocevic E, Svendsen SW, Joørgensen KT, Frost P, Bonde JP. Occupational lifting, fetal death and preterm birth: Findings from the Danish National Birth Cohort using a job exposure matrix. PLoS ONE. 2014;9(3):e90550. Quansah R, Gissler M, Jaakkola JJ. Work as a nurse and a midwife and adverse pregnancy outcomes: a Finnish nationwide population-based study. Journal of women's health (2002). 2009;18(12):2071-6. Tennant PW, Rankin J, Bell R. Maternal body mass index and the risk of fetal and infant death: a cohort study from the North of England. Human Reproduction. 2011;26(6):1501-11. Yao R, Park BY, Foster SE, Caughey AB. The association between gestational weight gain and risk of stillbirth: a population-based cohort study. Annals of Epidemiology. 2017;27(10):638-44. Government of South Australia. Obese Obstetric Woman - Management in South Australia 2019 Clinical Directive. SA Health.2019. Table 2 and 3 Table 2 and 3 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files STROBEchecklistv4StillbirthoddsinSouthAustralia.docx Table2and3.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 11 Apr, 2024 Reviews received at journal 11 Apr, 2024 Reviews received at journal 09 Apr, 2024 Reviewers agreed at journal 09 Apr, 2024 Reviewers agreed at journal 09 Apr, 2024 Reviewers invited by journal 08 Apr, 2024 Editor invited by journal 22 Mar, 2024 Editor assigned by journal 21 Mar, 2024 Submission checks completed at journal 21 Mar, 2024 First submitted to journal 13 Mar, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4096693","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":282853141,"identity":"0092b2ca-36ab-4939-9d18-5bd3212941bc","order_by":0,"name":"Anneka Bowman","email":"data:image/png;base64,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","orcid":"","institution":"University of Adelaide","correspondingAuthor":true,"prefix":"","firstName":"Anneka","middleName":"","lastName":"Bowman","suffix":""},{"id":282853142,"identity":"769fccb7-3b13-446b-9ffd-44bd2ad07596","order_by":1,"name":"Thomas Sullivan","email":"","orcid":"","institution":"South Australian Health and Medical Research 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Network","correspondingAuthor":false,"prefix":"","firstName":"Cathy","middleName":"","lastName":"Leane","suffix":""},{"id":282853153,"identity":"07e41cdb-c94c-4aed-b27c-a09d5f0febe9","order_by":8,"name":"Philippa Middleton","email":"","orcid":"","institution":"South Australian Health and Medical Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Philippa","middleName":"","lastName":"Middleton","suffix":""}],"badges":[],"createdAt":"2024-03-14 02:29:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4096693/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4096693/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":53372245,"identity":"2da9be3d-8a4c-4cc5-9cac-519398163ab1","added_by":"auto","created_at":"2024-03-25 08:13:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":554250,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4096693/v1/e8e79909-d5b4-4f0f-bf96-e4bfac687747.pdf"},{"id":53371606,"identity":"4b651570-57b0-4ba5-93e3-babd84227f8f","added_by":"auto","created_at":"2024-03-25 08:05:34","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":39482,"visible":true,"origin":"","legend":"","description":"","filename":"STROBEchecklistv4StillbirthoddsinSouthAustralia.docx","url":"https://assets-eu.researchsquare.com/files/rs-4096693/v1/14f5be9a97a2ea9345152c18.docx"},{"id":53371605,"identity":"04051994-e200-4ceb-91ea-846acb90d597","added_by":"auto","created_at":"2024-03-25 08:05:34","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":55161,"visible":true,"origin":"","legend":"","description":"","filename":"Table2and3.docx","url":"https://assets-eu.researchsquare.com/files/rs-4096693/v1/e0dd157d0bb0273d8cc351ee.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Lifestyle and sociodemographic risk factors for stillbirth by region of residence in South Australia: a retrospective cohort study","fulltext":[{"header":"Background","content":"\u003cp\u003eGlobally, more than 2.64\u0026nbsp;million babies are stillborn annually, with the highest rates occurring in low- and middle-income countries (LMICs) (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). In high-income countries (HICs), preventable stillbirths continue to be of concern, with slow progress towards global targets for rate reduction. To address this issue, the Australian government appointed a Senate Select Committee on Stillbirth Research and Education in 2018 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Their report revealed that Australia had \u0026lsquo;slipped\u0026rsquo; in its progress to reduce stillbirth rates in line with targets compared with other HICs. It also demonstrated that babies born to mothers living remotely were more likely to be stillborn than babies born in major cities (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). In 2020, \u003cem\u003eWomen and Birth\u003c/em\u003e published a series focused on stillbirth in Australia and identified the national action required to decrease rates (\u003cspan additionalcitationids=\"CR6 CR7 CR8\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Rumbold et al. (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) highlighted the impact of inequity on stillbirth rates within select Australian populations, noting particular concern within communities experiencing isolation and socioeconomic disadvantage (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Numerous risk factors in disadvantaged communities contribute to the widening gap in health inequality, further hindering stillbirth prevention (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). This research aims to identify lifestyle and sociodemographic risk factors for stillbirth in South Australia (SA) geographically and to explore these risks according to remoteness.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design and setting\u003c/h2\u003e \u003cp\u003eThis was a retrospective state-wide observational cohort study using the SA perinatal outcomes dataset, including all births from 1998 to 2016 (cohort one). The dataset contains pregnancy outcomes categorised as live birth or stillbirth. The data were obtained anonymously, with all identifying fields removed prior to their provision for research purposes. The study concept, acceptability, methods and interim analysis were presented, reviewed, and approved by the NHMRC Centre for Research Excellence in Stillbirth Indigenous Advisory Committee at two separate timepoints. The final manuscript was reviewed and approved by local SA Indigenous researchers and senior health care advisors prior to submission.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eMaterials\u003c/h2\u003e \u003cp\u003eIn SA, all births are reported by midwives, birth attendants and obstetricians in standardised supplementary birth records. The SA Perinatal Outcomes Unit integrates continuous validation of the dataset by comparing data collected from the supplementary birth records to electronic hospital records at the time of coding. Sociodemographic characteristics and pregnancy and birth outcome data were recorded. Due to the later introduction of BMI to the data collection, analyses involving BMI were restricted to the years 2007\u0026ndash;2016 (cohort two). Terminations of pregnancy were excluded.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eDefinitions and Outcomes\u003c/h2\u003e \u003cp\u003eVariable definitions and time periods are provided in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Information for all births (live or stillborn)\u0026thinsp;\u0026ge;\u0026thinsp;20 weeks gestational age (GA) of \u0026ge;\u0026thinsp;400 grams at birth are reported. The primary outcome, stillbirth, was defined in line with the standard Australian Institute of Health and Wellbeing definition as the birth of a baby showing no signs of life at \u0026ge;\u0026thinsp;20 weeks\u0026rsquo; completed GA, or \u0026ge;\u0026thinsp;400 grams birthweight where no GA is provided.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eStudy variables included, timepoint of collection and definition of each variable\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable (availability)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTime point of collection\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDefinition/Categorisation\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStudy Variables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal ethnicity (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFirst antenatal visit (booking visit)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSelf-reported Caucasian, Aboriginal, Torres Strait Islander, Aboriginal and Torres Strait Islander or Asian status. Aboriginal and/or Torres Strait Islander status includes identification by Aboriginal or Torres Strait Islander descent, self-identification of community acceptance of Aboriginal and/or TSI status. Births to women recorded as Aboriginal, Torres Strait Islander, and/or Aboriginal were categorised as Aboriginal and/or Torres Strait Islander women for analysis. Women recorded as Asian were categorised as Asian, and women recorded as Caucasian were categorised as Caucasian.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCountry of birth (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFirst antenatal visit (booking visit)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAustralia, Oceania, Europe/USSR, Middle East/Nth Africa, SE Asia, NE Asia, Southern Asia, Nth America, South/Central America, Africa as reported by women.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStatistical areas Level 3 (SA3) areas (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePlace of usual residence data. Australia Bureau of Statistics modified Accessibility and Remoteness Index of Australia (ARIA+) score average for each SA3 area compiled from SA2 area ARIA\u0026thinsp;+\u0026thinsp;scores. SA3 area was assigned on maternal usual place of residence at birth. Areas were classified as; major cities (geographic distance imposes minimal restrictions upon accessibility to the widest range of goods, services and opportunities for social interaction), inner regional areas (geographic distance imposes some restrictions upon accessibility to the widest range of goods, services and opportunities for social interaction), outer regional areas (geographic distance imposes a moderate restriction upon accessibility to the widest range of goods, services and opportunities for social interaction), remote/very remote areas (geographic distance imposes the highest restriction upon accessibility to the widest range of goods, services and opportunities for social interaction). Map of South Australia areas according to the ABS modified ARIA\u0026thinsp;+\u0026thinsp;score with superimposed SA3 boundaries shown below (Fig.\u0026nbsp;1).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAdequacy of antenatal care access (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAdequacy of antenatal care was assessed per pregnancy according to the Australian Clinical Practice Guidelines: Pregnancy Care that recommends nulliparous women have a minimum of 10 antenatal visits, and multiparous women; a minimum of 7 antenatal visits (40). Adequacy was assigned separately by parity (nulliparous and multiparous) stratified by gestational age.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal age (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCategories: 12\u0026ndash;19 years, 20\u0026ndash;24 years, 25\u0026ndash;29 years, 30\u0026ndash;34 years, 35\u0026ndash;40 years, \u0026ge;\u0026thinsp;40 years\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarital status (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCategories: Married/Unmarried (encompasses; never married, widowed, divorced, separated)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoking status (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFirst antenatal visit (booking visit) and again at 20 weeks GA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-smokers as self-reported smoking status at booking visit and 20 weeks GA. Women were classified as smokers if any smoking was reported at either visit.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParity (1998\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFirst antenatal visit (booking visit)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNulliparous, multiparous\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChronic health medical conditions\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePrevious diabetes or chronic hypertension\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParental occupation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFather\u0026rsquo;s occupation at birth, mother occupation prior to and/or during pregnancy before \u0026lsquo;home duties\u0026rsquo;.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOne of 13 occupation groups according to the ABS Australia Standard Classification of Occupations (ASCO) first edition\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInter-pregnancy interval\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCalculated as the number of months between the previously recorded birth, and date of conception of the current pregnancy (\u0026gt;\u0026thinsp;6 months, \u0026lt; 6 months).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal BMI (2007\u0026ndash;2016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFirst antenatal visit (booking visit) measurements\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCalculated as weight in kgs divided by height (in meters) squared. Underweight (\u0026lt;\u0026thinsp;19), healthy (\u003cspan additionalcitationids=\"CR20 CR21 CR22 CR23\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e), overweight (\u003cspan additionalcitationids=\"CR26 CR27 CR28\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e) and class 1 obesity (30\u0026ndash;34 years), class 2 obesity (35\u0026ndash;39 years), morbid obesity (40+)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnaemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt any stage during pregnancy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAnaemia diagnosed as maternal Hb\u0026thinsp;\u0026lt;\u0026thinsp;10gms/100ml\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eStudy Confounders\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObstetric conditions\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePlacental abruption, multiple pregnancy, post-term birth (\u0026gt;\u0026thinsp;41 completed weeks GA)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eProlonged labour\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLabour duration of \u0026gt;\u0026thinsp;18 hrs\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePast obstetric history\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePrevious caesarean section, previous stillbirth.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedical conditions\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAsthma during pregnancy, urinary tract infection during pregnancy\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBabies born small for gestational age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAfter birth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSGA; below the 10th percentile were determined using Australian national birthweight percentiles estimated from a large Australian cohort of infants born between 1997 and 2007 (41).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eRural and remote living at birth status was based on statistical areas level 3 (SA3) data associated with each birth. Australia Bureau of Statistics modified Accessibility and Remoteness Index of Australia (ARIA+) score average for each SA3 area compiled from SA2 area ARIA\u0026thinsp;+\u0026thinsp;scores. The areas were classified as: major cities, inner regional areas, outer regional areas, or remote/very remote areas. When exposure data or variable data were missing, individual births were excluded from the analysis.\u003c/p\u003e \u003cp\u003e[Insert Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e here]\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eVariables were categorised as outlined in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Categories with \u0026lt;\u0026thinsp;10 stillbirths per group were reported as \u0026lsquo;\u0026lt; 10\u0026rsquo;, and crude odds ratios (ORs) concealed. Within multivariable analysis where categories had fewer than five stillbirths, analyses are reported as \u0026lsquo;\u0026lt; 5\u0026rsquo;. Logistic regression was performed using the statistical software STATA 16 IC (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e) to determine associations between potential risk factors and stillbirth, described using odds ratios (ORs) and 95% confidence intervals (95% CIs). Unadjusted and adjusted models were considered, with adjustments made for variables that demonstrated significance during univariate analysis (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). For each risk factor, adjustment variables included year of birth, adequate antenatal care (ANC) access (adjusted for GA at birth), marital status, ethnicity, smoking status, parity, remote/rural status, age, previous stillbirth, medical conditions (preexisting diabetes, hypertension, anaemia), plurality, interpregnancy interval, insurance status, and obstetric complications (gestational diabetes, gestational hypertension, antepartum haemorrhage [APH]). The cohort was stratified by residential remoteness, and the analysis was repeated using the same adjustment variables (excluding rural/remote status). Factors demonstrating the strongest association with stillbirth odds were further explored to calculate SA-specific population attributable fractions (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e) and annual attributable stillbirths per factor (n). The analysis was repeated for cohort two, which was additionally adjusted for BMI (Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e4\u003c/span\u003e and \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultivariable analysis of risk factors and their association with stillbirth odds in SA, between 2007 and 2016 (cohort two).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAdjusted OR\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoking\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNon-smoker\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSmoker\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.16 (0.95, 1.42)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInsurance type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePrivate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePublic\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.82 (0.65, 1.03)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarital Status\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMarried\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUnmarried\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.23 (0.97, 1.55)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAdequate ANC access\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAdequate antenatal care access\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInadequate antenatal care access\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e4.02 (3.19, 5.06)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal age\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12\u0026ndash;19 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.20 (0.81, 1.78)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20\u0026ndash;24 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.98 (0.76, 1.27)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25\u0026ndash;29 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u0026ndash;34 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.07 (0.96, 1.32)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35\u0026ndash;39 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.17 (0.90, 1.51)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;40 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.00 (1.40, 2.86)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal occupation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eProfessionals/Managers/Admin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClerks/Sales people\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.02 (0.81, 1.29)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTradespersons/Labourers/Lab \u0026amp; machine operators\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.08 (0.75, 1.56)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eStudent\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.45 (0.97, 2.17)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUnemployed/Pensioner/Home duties\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.19 (0.93, 1.53)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePaternal occupation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eProfessionals/Managers/Admin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClerks/Salespeople\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.02 (0.73, 1.43)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTradespersons/Labourers/Lab \u0026amp; machine operators\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.10 (0.89, 1.36)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eStudent\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.13 (0.66, 1.93)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUnemployed/Pensioner/Home duties\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.46 (1.04, 2.07)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInterpregnancy interval\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026le;\u0026thinsp;6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.21 (0.90, 1.62)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCountry of birth*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAustralia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEurope/USSR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.14 (0.80, 1.63)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMiddle east/Nth Africa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.87 (1.23, 2.83)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSE Asia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.93 (0.62, 1.40)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNE Asia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.90 (0.54, 1.50)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSouthern Asia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.67 (1.24, 2.24)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNth America\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;5 SBs\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSouth/Central America\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;5 SBs\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAfrica\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.96 (1.30, 2.97)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOceania\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;5 SBs\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEthnicity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCaucasian\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAboriginal/Torres Strait Islander\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.17 (0.80, 1.72)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAsian\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.43 (1.13, 1.82)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNulliparous\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.80 (0.65, 1.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMultiparous\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRemoteness\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMajor City\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInner regional area\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.08 (0.83, 1.40)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOuter regional area\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.30 (0.97, 1.75)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRemote/Very remote area\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.36 (0.96, 1.91)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnaemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo anaemia during pregnancy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAnaemia during pregnancy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.17 (0.91, 1.52)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eaOR adjusted for year of birth, adequate ANC access, marital status, maternal BMI, maternal ethnicity, smoking status, parity, remote/rural status, maternal age, previous stillbirth, medical conditions (pre-existing diabetes or hypertension, anaemia), plurality, interpregnancy interval, insurance status, obstetric complications (gestational diabetes, gestational hypertension, APH)\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003e*maternal ethnicity excluded from model of adjustment\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultivariable analysis of risk factors and their association with stillbirth odds in SA, between 2007 and 2016, stratified by areas of remoteness (cohort two).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eMaternal BMI category\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTotal Births\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eStillbirth rate/1000 births\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCrude OR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAdjusted OR for risk factors of stillbirth*\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eAdjusted OR for risk factors of stillbirth stratified by region of residence**\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMajor city\u0026dagger;\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInner regional\u0026dagger;\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eOuter regional\u0026dagger;\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eRemote/very remote\u0026dagger;\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUnderweight (\u0026lt;\u0026thinsp;19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5,421\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.80 (0.50, 1.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.72 (0.44, 1.19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.66\u003c/p\u003e \u003cp\u003e(0.08, 5.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHealthy weight (\u003cspan additionalcitationids=\"CR20 CR21 CR22 CR23\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e67,664\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eReferent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOverweight (\u003cspan additionalcitationids=\"CR26 CR27 CR28\" citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45,594\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.99 (0.82, 1.19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.02 (0.84, 1.24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.44\u003c/p\u003e \u003cp\u003e(0.82, 2.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.96\u003c/p\u003e \u003cp\u003e(0.76, 1.20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.23\u003c/p\u003e \u003cp\u003e(0.60, 2.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1.10\u003c/p\u003e \u003cp\u003e(0.54, 2.26)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObese class 1 (\u003cspan additionalcitationids=\"CR31 CR32 CR33\" citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22,518\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.15 (0.96, 1.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.06 (0.82, 1.36)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.06\u003c/p\u003e \u003cp\u003e(0.50, 2.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e\u003cb\u003e1.33\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(1.05, 1.68)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e1.39\u003c/p\u003e \u003cp\u003e(0.67, 2.86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.69\u003c/p\u003e \u003cp\u003e(0.28, 1.70)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eObese class 2 (35\u0026ndash;39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10,426\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1.38 (1.04, 1.83)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e1.48 (1.08, 2.02)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.24\u003c/p\u003e \u003cp\u003e(0.49, 3.12)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMorbidly Obese (40+)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6,750\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.28 (0.91, 1.08)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.29 (0.89, 1.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.99 (0.34, 2.92)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMissing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42,228\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e* aOR adjusted for year of birth, adequate ANC access, marital status, rural/remote status, maternal ethnicity, smoking status, parity, maternal age (\u0026lt;\u0026thinsp;35, 35\u0026ndash;39, \u0026gt;\u0026thinsp;40), previous stillbirth, medical conditions (pre-existing diabetes or hypertension, anaemia), plurality, interpregnancy interval, insurance status, obstetric complications (gestational diabetes, gestational hypertension, APH)\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e** aOR adjusted for year, adequate ANC access, marital status, smoking status, parity, maternal age, previous stillbirth, medical conditions (pre-existing diabetes or hypertension, anaemia), plurality, interpregnancy interval, insurance status, obstetric complications (gestational diabetes, gestational hypertension, APH)\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e\u0026dagger;stratified analysis conducted using populations designated as living within a major city (n\u0026thinsp;=\u0026thinsp;110,075 (407 stillbirths)), Inner regional area (n\u0026thinsp;=\u0026thinsp;19,569 (73 stillbirths)), outer regional area (n\u0026thinsp;=\u0026thinsp;11,363 (51 stillbirths), or remote/very remote area (n\u0026thinsp;=\u0026thinsp;7795 (40 stillbirths)). Due to cohort size, BMI categories were grouped (healthy (BMI\u0026thinsp;\u0026lt;\u0026thinsp;25), overweight (BMI 25\u0026ndash;29), obese (BMI\u0026thinsp;\u0026gt;\u0026thinsp;30)).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eData were available for 363,933 births in SA including 1767 stillborn babies following exclusions (Table \u003cspan\u003e2\u003c/span\u003e). Birthing people were predominantly Australian born (81%) with 86% of Australian born people identifying as Caucasian. The majority (71%) lived in major cities, followed by inner regional areas (14%), outer regional areas (8%) and remote or very remote areas (6%). During pregnancy, 13.5% of birthing people access less than the recommended number of ANC visits (Australian Clinical Practice Guidelines: Pregnancy Care recommends that nulliparous women have a minimum of 10 and multiparous women have a minimum of 7). Most birthing people were nonsmokers (78%) and gave birth in the Australian public health care system (70%) (Table\u0026nbsp;\u003cspan\u003e2\u003c/span\u003e). Cohort two included 201,315 births (918 stillborn babies) between 2007 and 2016.\u003c/p\u003e\n\u003cdiv\u003e\n\u003c/div\u003e\n\u003cp\u003e[Insert Table\u0026nbsp;\u003cspan\u003e2\u003c/span\u003e here]\u003c/p\u003e\n\u003cp\u003eThe stillbirth rate in SA over the study period was 4.85/1000 births. Stillbirth rates were highest for birthing people who had inadequate ANC access (13.78/1000 births) and those who reported that they (8.78/1000 births) or their partner were a \u0026lsquo;pensioner\u0026rsquo; (10.21/1000 births). Stillbirths were high among \u0026lsquo;unemployed\u0026rsquo; individuals and \u0026lsquo;plant or machine operators\u0026rsquo; (8.15 and 7.97/1000 births, respectively), those aged less than 19 or over 40 (7.51 and 7.71/1000 births, respectively), and those who were unmarried (7.63/1000 births) or smoked (6.20/1000 births). Stratification by remoteness status suggested that rates of stillbirth differed minimally by remoteness classification (Table\u0026nbsp;\u003cspan\u003e3\u003c/span\u003e).\u003c/p\u003e\n\u003cdiv\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\"\u003e\n \u003ch2\u003eAdequacy of antenatal care access (ANC)\u003c/h2\u003e\n \u003cp\u003eCrude analysis demonstrated a fourfold increase in stillbirth odds for birthing people who received inadequate ANC compared with those who received adequate ANC (Table \u003cspan\u003e2\u003c/span\u003e). This increased odds of stillbirth with inadequate ANC access was observed across all areas of residence (Table \u003cspan\u003e3\u003c/span\u003e). Adjusted analysis demonstrated that birthing people in SA who experienced inadequate versus adequate ANC access had fivefold greater odds of stillbirth (inner region: aOR 5.56; 95% CI 3.91\u0026ndash;7.92; remote/very remote region: aOR 4.64; 95% CI 2.98\u0026ndash;7.23).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec9\"\u003e\n \u003ch2\u003eParental occupation\u003c/h2\u003e\n \u003cp\u003eCrude analysis indicated that several occupations were associated with stillbirth. Through multivariable analysis, birthing people who worked as plant/machine operators had almost double the odds of stillbirth versus professionals (aOR 1.99; 95% CI 1.16\u0026ndash;3.43). Compared with professionals, unemployed birthing people also had increased odds of stillbirth (aOR 1.34; 95% CI 1.01\u0026ndash;1.79). No clear differences were noted in the area stratified analysis considering unemployment (compared with major cities, outer regional areas: aOR 1.59; 95% CI 0.63\u0026ndash;4.03, remote/very remote areas: aOR 1.35; 95% CI 0.54\u0026ndash;3.39).\u003c/p\u003e\n \u003cp\u003eUnemployed nonbirthing parent status (aOR 1.33; 95% CI 1.01\u0026ndash;1.76) and pensioner status (aOR 1.83; 95% CI 1.12\u0026ndash;2.99) versus professional status were associated with increased odds of stillbirth. Non-birthing parent tradeperson status (aOR 1.69; 95% CI 1.17\u0026ndash;6.16) and unemployment (aOR 4.06; 95% CI 1.41\u0026ndash;11.73) was independently associated with stillbirth within remote/very remote areas of SA (Table \u003cspan\u003e3\u003c/span\u003e).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\"\u003e\n \u003ch2\u003eBirthing persons\u0026rsquo; country of birth\u003c/h2\u003e\n \u003cp\u003eCrude analysis demonstrated increased odds of stillbirth for birthing people born in Southern Asia, the Middle East/North Africa, and Africa versus Australia (Table \u003cspan\u003e2\u003c/span\u003e). Increased odds of stillbirth were shown for birthing people from Southern Asia (versus Australia) (aOR 1.58; 95% CI 1.19\u0026ndash;2.10). This was mirrored for South Asian-born birthing people residing in major cities (Table \u003cspan\u003e3\u003c/span\u003e). Crude analysis revealed greater stillbirth odds for birthing people born in Middle Eastern/North African countries; however, this increase was attenuated in multivariable analyses. Similar results were shown for birthing people from African countries (64% increased odds of stillbirth) (versus Australia); however, the odds were attenuated in the multivariate analysis (aOR 0.82; 95% CI 0.29\u0026ndash;2.27). The odds of stillbirth did not increase for any of the other countries in which the birthing people were born compared with those for which the birthing people were born in Australia.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec11\"\u003e\n \u003ch2\u003eBirthing persons\u0026rsquo; ethnicity\u003c/h2\u003e\n \u003cp\u003eAboriginal and/or Torres Strait Islander status (versus Caucasian status) was shown to increase stillbirth odds through crude and adjusted analyses (cOR 2.55; 95% CI 2.11\u0026ndash;3.08, and aOR 1.50; 95% CI 1.20\u0026ndash;1.88). Stratification by place of residence revealed that the odds of stillbirth for Aboriginal and/or Torres Strait Islander versus Caucasian people were almost double within inner regional (aOR 1.91; 95% CI 1.06\u0026ndash;3.46) and remote/very remote areas (aOR 1.90; 95% CI 1.12\u0026ndash;3.21). Self-reported Asian ethnicity (versus Caucasian status) did not show an increase in stillbirth odds (aOR 1.12; 95% CI 0.93\u0026ndash;1.35). Stratification by areas of remoteness could not be performed due to small case numbers per subgroup.\u003c/p\u003e\n \u003cp\u003e[Insert Table\u0026nbsp;\u003cspan\u003e3\u003c/span\u003e here]\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\"\u003e\n \u003ch2\u003eBMI (cohort two)\u003c/h2\u003e\n \u003cp\u003eSimilar to cohort one, analyses of cohort two demonstrated increased odds of stillbirth with inadequate ANC access, particular parental occupations, and certain birthing person\u0026rsquo;s country of birth and ethnicity (Table \u003cspan\u003e4\u003c/span\u003e). Birthing person BMI was associated with marginally increased odds of stillbirth for BMI\u0026rsquo;s between 35 and 39 at the first antenatal appointment (Table\u0026nbsp;\u003cspan\u003e5\u003c/span\u003e). These findings were mirrored through remoteness stratification analysis. The odds of stillbirth were not significant for morbidly obese birthing people according to the analysis, possibly reflecting an underpowered sample size in this category. Through models adjusted for BMI, the associations between Aboriginal and/or Torres Strait Islander ethnicity and stillbirth odds decreased, eliminating this factor\u0026rsquo;s independent association with stillbirth.\u003c/p\u003e\n \u003cp\u003e[Insert Tables\u0026nbsp;\u003cspan\u003e4\u003c/span\u003e and \u003cspan\u003e5\u003c/span\u003e here]\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\"\u003e\n \u003ch2\u003ePopulation Attributable Fractions (PAFs) (Table\u0026nbsp;\u003cspan\u003e6\u003c/span\u003e)\u003c/h2\u003e\n \u003cdiv\u003e\n \u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 6\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eMultivariable analysis for select risk factors for birthing people residing in South Australia between 1998 and 2016, the population attributable fractions (PAF), and attributable stillbirths* (cohort one)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eaOR (95% CI)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePAF (%)**\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTotal preventable SB for study period (1998\u0026ndash;2016) (births)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAverage preventable SB per year in SA (births)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking status\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNon-smoker\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReferent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSmoker\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.13 (0.99, 1.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.31%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdequate ANC access\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAdequate ANC access\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReferent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eInadequate ANC access\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.93 (3.41, 4.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.65%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e437\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal age\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026le;\u0026thinsp;35 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReferent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026gt;\u0026thinsp;35 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.40 (1.23, 1.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.32%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal Occupation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll other occupations\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReferent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePlant or machine operators\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.74 (1.04, 2.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.40%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal country of birth\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll other countries (excluding only population of interest below)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReferent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSouthern Asian countries\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.64 (1.23, 2.18)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAfrican countries\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.55 (1.21, 1.99)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.52%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eRemoteness\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMajor city/Inner regional\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReferent\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e..\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOuter regional/remote/very remote\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.23 (1.08, 1.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.24%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e*SB\u0026thinsp;=\u0026thinsp;stillbirths, Remoteness\u0026thinsp;=\u0026thinsp;remoteness classification of the maternal residential postcode at the time of birth, aOR\u0026thinsp;=\u0026thinsp;adjusted odds ratio, odds adjusted for year of birth, adequate ANC access, marital status, smoking status, parity, remoteness, maternal age, maternal pre-existing medical conditions (diabetes, hypertension, anaemia), insurance status, interpregnancy interval, plurality, gestational diabetes or hypertension, antepartum haemorrhage (adjustments of individual factors exclude the factor of interest within adjustment).\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e**PAF calculated using methods described by Mansournia et al (\u003cspan\u003e13\u003c/span\u003e)\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eFactors with the strongest independent associations with stillbirth odds were selected to determine PAFs (Table \u003cspan\u003e6\u003c/span\u003e). The PAF enabled examination of the direct percentage of stillbirths attributed to each risk factor within the population according to the populational prevalence. The factors with the greatest impacts on stillbirth rates in SA were inadequate ANC access (PAF: 27.65%) and birthing person age\u0026thinsp;\u0026gt;\u0026thinsp;35 years (PAF: 6.32%). The PAFs for smoking and age\u0026thinsp;\u0026gt;\u0026thinsp;35 years were 3.31% and 6.32%, respectively.\u003c/p\u003e\n \u003cp\u003e[Insert Table\u0026nbsp;\u003cspan\u003e6\u003c/span\u003e]\u003c/p\u003e\n \u003cp\u003eAdequate ANC access in Australia has been highlighted as a marker of inequity between areas of remoteness and major cities (\u003cspan\u003e3\u003c/span\u003e) and is well established as the best means to ensure a healthy pregnancy and effective preventative care for poor pregnancy outcomes. Our results suggest that inadequate ANC access (as per the Australian pregnancy care guidelines (\u003cspan\u003e13\u003c/span\u003e)) is strongly associated with increased odds of stillbirth. The recommended number of ANC visits is 10 for first pregnancies and seven for subsequent uncomplicated pregnancies (\u003cspan\u003e13\u003c/span\u003e). PAF calculations indicated that if all recommended appointments were accessible to all birthing people, 437 stillbirths could have been prevented over this study period, equating to an average of 24 stillbirths per year. Previous research examining the impact of ANC on stillbirths has revealed a U-shaped curve and has suggested that 14 visits is optimal to minimise risk (\u003cspan\u003e14\u003c/span\u003e). Globally, there are notable variations in the minimum number of visits recommended; German studies suggest 12 (\u003cspan\u003e15\u003c/span\u003e), USA, 11 (\u003cspan\u003e16\u003c/span\u003e), and Canada (\u003cspan\u003e17\u003c/span\u003e, \u003cspan\u003e18\u003c/span\u003e). Strategies to encourage improved ANC access, such as culturally safe care models, and addressing travel and financial barriers to access, alongside further consideration of an increase in the minimum number of recommended ANC visits in Australia, should constitute part of stillbirth prevention efforts.\u003c/p\u003e\n \u003cp\u003eRemote and rural status has previously been shown to have an independent association with intrapartum stillbirth in remote Western Australia due to a lack of access to high-level care during labour, although Aboriginal and/or Torres Strait Islander women were excluded from these findings because the main outcome focused on migrant women in Western Australia (\u003cspan\u003e19\u003c/span\u003e). Comparable results have been shown in studies examining the impact of regional and remote living on stillbirth rates in Australia (\u003cspan\u003e20\u003c/span\u003e, \u003cspan\u003e21\u003c/span\u003e), although the findings were limited by cohort size and limited confounder adjustment. Our analysis revealed marginally greater odds of stillbirth within regional areas (i.e., the outer and inner regional areas), and for birthing people who smoked during pregnancy, who were unmarried or of advanced age (over 35 years). Aboriginal and/or Torres Strait Islander birthing people were at increased risk of stillbirth in inner and outer regional areas. These findings further highlight the need for increased preventative care for those living in regional and remote areas.\u003c/p\u003e\n \u003cp\u003eThere are mixed findings regarding the association between Aboriginal and/or Torres Strait Islander People and stillbirth odds. Some have reported increased odds of stillbirth, while others have reported equivalence (\u003cspan\u003e22\u003c/span\u003e, \u003cspan\u003e23\u003c/span\u003e). Our study suggested that Aboriginal and/or Torres Strait Islander birthing people are at risk of 21 stillbirths per year in SA. Compared with Caucasian birthing people, Aboriginal and/or Torres Strait Islander birthing people residing in inner regional and remote/very remote areas experience greater stillbirth odds than their city-dwelling counterparts. An analysis incorporating BMI into models of adjustment diminished this association, indicating that there was no independent association with stillbirth odds and that strategies to address BMI may be key. This may implicate a combined lack of culturally safe care models, limited birthing on country services, and poorly resourced ANC in regional and remote areas of SA. Cultural safety and birthing on country training of health care professionals has been shown to improve access for Aboriginal and/or Torres Strait Islander families, including trauma-informed care (\u003cspan\u003e24\u003c/span\u003e).\u003c/p\u003e\n \u003cp\u003eSouth Asian ethnicity has previously been shown to have an independent association with stillbirth odds in HIC populations globally (\u003cspan\u003e19\u003c/span\u003e, \u003cspan\u003e25\u003c/span\u003e\u0026ndash;\u003cspan\u003e30\u003c/span\u003e). Analyses of stillbirth odds for birthing people of South Asian ethnicity have differed when country of birth has been used as a proxy for ethnicity (\u003cspan\u003e19\u003c/span\u003e, \u003cspan\u003e22\u003c/span\u003e, \u003cspan\u003e26\u003c/span\u003e\u0026ndash;\u003cspan\u003e28\u003c/span\u003e, \u003cspan\u003e31\u003c/span\u003e) versus when self-reported ethnicity has been used (\u003cspan\u003e25\u003c/span\u003e, \u003cspan\u003e29\u003c/span\u003e, \u003cspan\u003e30\u003c/span\u003e). Although country of birth is a commonly used proxy for ethnicity, there is potential for misclassification. The findings of this study demonstrate that South Asian (versus Australian) countries of birth are associated with stronger odds of stillbirth than self-reported Asian (versus Caucasian) ethnicity. Country of birth should be considered an independent factor when assessing the risk of stillbirth at the individual level.\u003c/p\u003e\n \u003cp\u003eCertain occupations and their associated exposures to chemicals or lifting and rotating shift work have previously been implicated as contributors to stillbirth in HICs (\u003cspan\u003e32\u003c/span\u003e\u0026ndash;\u003cspan\u003e34\u003c/span\u003e). To our knowledge, there has been no prior research examining associations between stillbirth and occupational groups within an entire population. The increased odds of stillbirth for plant- or machine-operating birthing people warrants attention. As does paternal unemployment and tradesperson status in remote and very remote areas. \u0026ndash; both also associated with increased stillbirth odds in SA.\u003c/p\u003e\n \u003cp\u003eAccording to previous research on HICs, obesity consistently and independently increases stillbirth odds (\u003cspan\u003e31\u003c/span\u003e, \u003cspan\u003e35\u003c/span\u003e, \u003cspan\u003e36\u003c/span\u003e). Our findings demonstrated that a BMI between 35 and 39 was associated with increased odds of stillbirth, but this was not observed when the BMI reached\u0026thinsp;\u0026ge;\u0026thinsp;40. This observation may be due to the low number of birthing people with a BMI\u0026thinsp;\u0026ge;\u0026thinsp;40, rendering the analysis underpowered. However, the absence of increased stillbirth odds for birthing people with a BMI\u0026thinsp;\u0026ge;\u0026thinsp;40 could be due to the different care pathways and tailored care and monitoring for this group. In SA, at their first antenatal appointment, this group is provided specific ANC programs focused on pregnancy risks and complications associated with morbid obesity (\u003cspan\u003e37\u003c/span\u003e).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\"\u003e\n \u003ch2\u003eStrengths and Limitations\u003c/h2\u003e\n \u003cp\u003eThe strengths of this study lie in the comprehensive and detailed measures for each birth, including the inclusion of parental occupational coding and ethnicity alongside country of birth. Factors included within this dataset are collected routinely for the entire study period without changes in the definition or classification of diseases. Due to the large number of stillbirths included in this study, analysis of many factors was possible, allowing meaningful and generalisable results. However, we acknowledge several limitations. The omission of BMI data collected prior to 2007 prevented the analysis of BMI across the study period. Cohort two encompasses BMI, but due to the smaller cohort size, comprehensive analysis was not possible. This study has the same limitations ubiquitous to research examining routinely collected perinatal data, which may not have been intended solely for research purposes. The lack of data concerning domestic assault, pollution, consanguinity, sleep position and drug/alcohol use leaves potential for residual bias due to unmeasured covariates. The current analysis does not account for the temporal changes in individual factors\u0026rsquo; impacts over the course of the study period. The use of average ARIA\u0026thinsp;+\u0026thinsp;scores from SA2\u0026rsquo;s encompassed within each SA3 for remoteness status has the potential to result in misclassification of remoteness status for some populations within assigned categories.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis research presents a robust and comprehensive analysis of a large SA cohort spanning almost two decades. Our findings highlight gaps in national- and state/territory-level analysis of stillbirth. By omitting stratification by remoteness, previous research has masked disparities between marginalised groups within regions that are shown to have the highest rates of stillbirth. Although this disparity has been well established and highlighted as a focus of addressing preventable stillbirth, further research stratified by remoteness is needed. It is clear from our findings that the stillbirth odds for birthing people aged 35\u0026ndash;40 years or with specific occupations differ according to remoteness classification, although smaller populations living in regional and remote areas render our analysis underpowered for some factors. Through robust subanalysis incorporating comprehensive multivariable adjustment (including BMI), our findings demonstrate that birthing person Aboriginal and/or Torres Strait Islander status is not independently associated with stillbirth, and while there is no independent association, holistic and culturally safe care is essential. Improved access to care will aid in addressing factors that may be independently associated with and contributing to stillbirth rates within this population. Efforts are required to ensure that birthing people have adequate ANC access, and this may require review through national care guidelines. Although current pregnancy care guidelines and policies are rigorous and based on evidence at the national level, areas of ambiguity and differences exist for health care providers in regional and remote areas, which are overlaid with finite access to resources. Our findings indicate that adequate ANC access is the greatest risk factor for stillbirth in remote SA. Complexities preventing engagement in care and poor attendance may reflect access to and acceptability of ANC programs across all facets of society. Limitations of national policy and guidelines for ANC access in regional and remote areas result in care that is complex to deliver within limited resource settings, often with limited accessibility. The evidence presented indicates that further research is needed to determine the required minimum number of ANC visits and to suggest a focus on providing adequate access to the recommended number of ANC visits for all birthing people. This also needs to take into consideration the implications for current health care systems, especially in remote and regional areas.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u0026nbsp;\u003c/strong\u003eEthical approval was granted from the SA Department of Health and Wellbeing Committee (ID HREC19SAH13) on 11\u003csup\u003eth\u003c/sup\u003e of June 2019, and the Aboriginal Health Council of SA Human Research Ethics Committee (ID 04-19-816) on the 8\u003csup\u003eth\u003c/sup\u003e of May 2019. Participant consent was not an ethical requirement for this research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003enot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003eThe deidentified data analysed are not publicly available, but requests to the corresponding author for the data will be considered on a case-by-case basis in discussion with the South Australian Data Custodian. Requests may be referred to the South Australian Data Custodian to obtain approval.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e The authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e No funding was received for this research outside of the primary authors affiliated organisations. Funding was granted for this project in the form of research training stipends (University of Adelaide) and PhD top-up scholarships (Stillbirth Centre of Research Excellence) for A Bowman during the course of their higher degree by research.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions AB:\u003c/strong\u003e Conceptualisation, Data curation, Formal Analysis, Funding acquisition, Project administration, Software, Methodology, Writing \u0026ndash; original draft, Interpretation of data\u0026nbsp;\u003cstrong\u003eTS:\u003c/strong\u003e Formal Analysis, Methodology, Supervision, Validation, Writing \u0026ndash; review and editing\u0026nbsp;\u003cstrong\u003eVF:\u003c/strong\u003e Conceptualisation, Methodology, Supervision, Writing \u0026ndash; review and editing, Analysis and interpretation of data\u0026nbsp;\u003cstrong\u003eMM:\u003c/strong\u003e Conceptualisation, Data curation, Resources, Software, Supervision, Writing \u0026ndash; review and editing\u0026nbsp;\u003cstrong\u003eES:\u003c/strong\u003e Writing \u0026ndash; review and editing, Methodology, Interpretation of the data\u0026nbsp;\u003cstrong\u003eCL:\u003c/strong\u003e Writing \u0026ndash; review and editing, Analysis and interpretation of data\u0026nbsp;\u003cstrong\u003eDSB:\u003c/strong\u003e Conceptualisation, Supervision, Writing \u0026ndash; review and editing, Analysis and interpretation of data\u0026nbsp;\u003cstrong\u003eKH:\u0026nbsp;\u003c/strong\u003eSupervision, Writing \u0026ndash; review and editing, Analysis and interpretation of data\u0026nbsp;\u003cstrong\u003ePM:\u003c/strong\u003e Conceptualisation, Methodology, Software, Supervision, Writing \u0026ndash; original draft, Writing \u0026ndash; review and editing, Analysis and interpretation of data\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u0026nbsp;\u003c/strong\u003eThe authors would like to acknowledge and thank SAHMRI Women and Kids for their support through this project, and also the Stillbirth Centre of Research Excellence for their financial support during the project. The University of Adelaide is also acknowledged for their financial support of the primary author during their higher degree by research of which this project forms a main component. Acknowledgement is also extended to the Stillbirth Centre of Research Excellence Indigenous Advisory Committee, and also the Aboriginal Communities and Families Health Research Alliance who assisted in guiding the objectives, and interpreting the results of this project. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eFlenady V, Koopmans L, Middleton P, Froen JF, Smith GC, Gibbons K, et al. Major risk factors for stillbirth in high-income countries: a systematic review and meta-analysis. The Lancet. 2011;377(9774):1331-40.\u003c/li\u003e\n\u003cli\u003eFr\u0026oslash;en JF, Cacciatore J, McClure EM, Kuti O, Jokhio AH, Islam M, et al. Stillbirths: why they matter. The Lancet. 2011;377(9774):1353-66.\u003c/li\u003e\n\u003cli\u003eGovernment. A. Response to: the Senate Select Committee on Stillbirth Research and Education Report. Canberra; 2019.\u003c/li\u003e\n\u003cli\u003eSelect Senate Committee on Stillbirth Research and Education. Select Committee on Stillbirth Research and Education Report: Stillbirth Research and Education. Parliment House, Canberra; 2018.\u003c/li\u003e\n\u003cli\u003eBoyle FM, Horey D, Dean JH, Loughnan S, Ludski K, Mead J, et al. Stillbirth in Australia 5: Making respectful care after stillbirth a reality: The quest for parent-centred care. Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):531-6.\u003c/li\u003e\n\u003cli\u003eEllwood DA, Flenady VJ. Stillbirth in Australia 6: The future of stillbirth research and education. 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Women and Birth : Journal of the Australian College of Midwives. 2020;33(6):520-5.\u003c/li\u003e\n\u003cli\u003eFox H, Topp SM, Lindsay D, Callander E. Ethnic, socio-economic and geographic inequities in maternal health service coverage in Australia. The International Journal of Health Planning and Management. 2021;36(6):2182-98.\u003c/li\u003e\n\u003cli\u003eStataCorp. Stata Statistical Software: Release 16. In: Station. C, editor. TX:: StataCorp LLC.; 2023.\u003c/li\u003e\n\u003cli\u003eMansournia MA, Altman DG. Population attributable fraction. British Medical Journal (Online). 2018;360:k757.\u003c/li\u003e\n\u003cli\u003eAustralian Government Department of Health. Clinical Practice Guidelines: Pregnancy Care. In: Australian Government Department of Health, editor. Canberra2020.\u003c/li\u003e\n\u003cli\u003eVintzileos AM, Ananth CV, Smulian JC, Scorza WE, Knuppel RA. Prenatal care and black-white fetal death disparity in the United States: Heterogeneity by high-risk conditions. Obstetrics and Gynecology. 2002;99(3):483-9.\u003c/li\u003e\n\u003cli\u003eReime B, Lindwedel U, Ertl KM, Jacob C, Schucking B, Wenzlaff P. Does underutilization of prenatal care explain the excess risk for stillbirth among women with migration background in Germany? Acta Obstetricia et Gynecologica Scandinavica. 2009;88(11):1276-83.\u003c/li\u003e\n\u003cli\u003ePartridge S, Balayla J, Holcroft CA, Abenhaim HA. Inadequate Prenatal Care Utilization and Risks of Infant Mortality and Poor Birth Outcome: A Retrospective Analysis of 28,729,765 U.S. Deliveries over 8 Years. American Journal of Perinatology. 2012;29(10):787-93.\u003c/li\u003e\n\u003cli\u003eHealth Nexus Best Start Resource Centre. Ontario Prenatal Education 2022 [Available from: https://www.ontarioprenataleducation.ca/routine-prenatal-care/.\u003c/li\u003e\n\u003cli\u003eHeaman MI, Martens PJ, Brownell MD, Chartier MJ, Derksen SA, Helewa ME. The Association of Inadequate and Intensive Prenatal Care With Maternal, Fetal, and Infant Outcomes: A Population-Based Study in Manitoba, Canada. J Obstet Gynaecol Can. 2019;41(7):947-59.\u003c/li\u003e\n\u003cli\u003eMozooni M, Pennell CE, Preen DB. Healthcare factors associated with the risk of antepartum and intrapartum stillbirth in migrants in Western Australia (2005-2013): A retrospective cohort study. PLoS Medicine. 2020;17(3):e1003061.\u003c/li\u003e\n\u003cli\u003eGraham S, Pulver LRJ, Wang YA, Kelly PM, Laws PJ, Grayson N, et al. The urban-remote divide for Indigenous perinatal outcomes. Medical Journal of Australia. 2007;186(10):509-12.\u003c/li\u003e\n\u003cli\u003eRobson S, Cameron CA, Roberts CL. Birth outcomes for teenage women in New South Wales, 1998-2003. Australian and New Zealand Journal of Obstetrics and Gynaecology. 2006;46(4):305-10.\u003c/li\u003e\n\u003cli\u003eGordon A, Raynes-Greenow C, McGeechan K, Morris J, Jeffery H. Risk factors for antepartum stillbirth and the influence of maternal age in New South Wales Australia: A population based study. BMC Pregnancy and Childbirth. 2013;13:12.\u003c/li\u003e\n\u003cli\u003eHodyl NA, Grzeskowiak LE, Stark MJ, Scheil W, Clifton VL. The impact of Aboriginal status, cigarette smoking and smoking cessation on perinatal outcomes in South Australia. Medical Journal of Australia. 2014;201(5):274-8.\u003c/li\u003e\n\u003cli\u003eKildea S, Hickey S, Barclay L, Kruske S, Nelson C, Sherwood J, et al. Implementing birthing on country services for Aboriginal and Torres Strait Islander families: RISE framework. Women and Birth. 2019;32(5):466-75.\u003c/li\u003e\n\u003cli\u003eBalchin I, Whittaker JC, Patel R, Lamont RF, Steer PJ. Racial variation in the association between gestational age and perinatal mortality: Prospective study. British Medical Journal. 2007;334(7598):833-5.\u003c/li\u003e\n\u003cli\u003eBerman Y, Ibiebele I, Patterson JA, Randall D, Ford JB, Nippita T, et al. Rates of stillbirth by maternal region of birth and gestational age in New South Wales, Australia 2004\u0026ndash;2015. Australian and New Zealand Journal of Obstetrics and Gynaecology. 2020;60(3):425-32.\u003c/li\u003e\n\u003cli\u003eDavies-Tuck ML, Davey MA, Wallace EM. Maternal region of birth and stillbirth in Victoria, Australia 2000-2011: A retrospective cohort study of Victorian perinatal data. PLoS ONE. 2017;12(6):e0178727.\u003c/li\u003e\n\u003cli\u003eDrysdale H, Ranasinha S, Kendall A, Knight M, Wallace EM. Ethnicity and the risk of late-pregnancy stillbirth. Medical Journal of Australia. 2012;197(5):278-81.\u003c/li\u003e\n\u003cli\u003eHeazell A, Li M, Budd J, Thompson J, Stacey T, Cronin RS, et al. Association between maternal sleep practices and late stillbirth - findings from a stillbirth case-control study. BJOG: An International Journal of Obstetrics and Gynaecology. 2018;125(2):254-62.\u003c/li\u003e\n\u003cli\u003eRavelli AC, Tromp M, Eskes M, Droog JC, van der Post JA, Jager KJ, et al. Ethnic differences in stillbirth and early neonatal mortality in The Netherlands. Journal of Epidemiology and Community Health. 2011;65(8):696-701.\u003c/li\u003e\n\u003cli\u003eGardosi J, Madurasinghe V, Williams M, Malik A, Francis A. Maternal and fetal risk factors for stillbirth: Population based study. British Medical Journal (Online). 2013;346(7893):f108.\u003c/li\u003e\n\u003cli\u003eBonde JP, J\u0026oslash;rgensen KT, Bonzini M, Palmer KT. Miscarriage and occupational activity: A systematic review and meta-analysis regarding shift work, working hours, lifting, standing, and physical workload. Scandinavian Journal of Work, Environment and Health. 2013;39(4):325-34.\u003c/li\u003e\n\u003cli\u003eMocevic E, Svendsen SW, Jo\u0026oslash;rgensen KT, Frost P, Bonde JP. Occupational lifting, fetal death and preterm birth: Findings from the Danish National Birth Cohort using a job exposure matrix. PLoS ONE. 2014;9(3):e90550.\u003c/li\u003e\n\u003cli\u003eQuansah R, Gissler M, Jaakkola JJ. Work as a nurse and a midwife and adverse pregnancy outcomes: a Finnish nationwide population-based study. Journal of women\u0026apos;s health (2002). 2009;18(12):2071-6.\u003c/li\u003e\n\u003cli\u003eTennant PW, Rankin J, Bell R. Maternal body mass index and the risk of fetal and infant death: a cohort study from the North of England. Human Reproduction. 2011;26(6):1501-11.\u003c/li\u003e\n\u003cli\u003eYao R, Park BY, Foster SE, Caughey AB. The association between gestational weight gain and risk of stillbirth: a population-based cohort study. Annals of Epidemiology. 2017;27(10):638-44.\u003c/li\u003e\n\u003cli\u003eGovernment of South Australia. Obese Obstetric Woman - Management in South Australia 2019 Clinical Directive. SA Health.2019.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table 2 and 3","content":"\u003cp\u003eTable 2 and 3 are available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"stillbirth, perinatal death, environment, pregnancy, reproductive health, risk","lastPublishedDoi":"10.21203/rs.3.rs-4096693/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4096693/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStillbirth rates remain a global priority and in Australia, progress has been slow. Risk factors of stillbirth are unique in Australia due to large areas of remoteness, and limited resource availability affecting the ability to identify areas of need and prevalence of factors associated with stillbirth. This retrospective cohort study describes lifestyle and sociodemographic factors associated with stillbirth in South Australia (SA), between 1998 and 2016.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll restigered births in SA between 1998 ad 2016 are included. The primary outcome was stillbirth (birth with no signs of life ≥ 20 weeks gestation or ≥ 400 grams if gestational age was not reported). Associations between stillbirth and lifestyle and sociodemographic factors were evaluated using multivariable logistic regression and described using adjusted odds ratios (aORs).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 363,959 births were included. Inadequate antenatal care access (assessed against the Australian Pregnancy Care Guidelines) was associated with the highest odds of stillbirth (aOR 3.93, 95% confidence interval (CI) 3.41–4.52). Other factors with important associations with stillbirth were plant/machine operation (aOR, 1.99; 95% CI, 1.16–2.45), birthing person age ≥ 40 years (aOR, 1.92; 95% CI, 1.50–2.45), paternal pensioner status (aOR, 1.83; 95% CI, 1.12–2.99), Asian country of birth (aOR, 1.58; 95% CI, 1.19–2.10) and Aboriginal/Torres Strait Islander status (aOR, 1.50; 95% CI, 1.20–1.88). The odds of stillbirth were increased in regional/remote areas in association with inadequate antenatal care (aOR, 4.64; 95% CI, 2.98–7.23), birthing age 35–40 years (aOR, 1.92; 95% CI, 1.02–3.64), Aboriginal and/or Torres Strait Islander status (aOR, 1.90; 95% CI, 1.12–3.21), paternal occupations: tradesperson (aOR, 1.69; 95% CI, 1.17–6.16) and unemployment (aOR, 4.06; 95% CI, 1.41–11.73).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFactors identified as independently associated with stillbirth odds include factors that could be addressed through timely access to adequate antenatal care and are likely relevant throughout Australia. The identified factors should be the target of stillbirth prevention strategies/efforts.\u003c/p\u003e\n\u003cp\u003eThe stillbirth rate in Australia is a national concern. Reducing preventable stillbirths remains a global priority.\u003c/p\u003e","manuscriptTitle":"Lifestyle and sociodemographic risk factors for stillbirth by region of residence in South Australia: a retrospective cohort study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-25 08:05:29","doi":"10.21203/rs.3.rs-4096693/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-04-11T16:06:18+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-04-11T09:06:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-04-09T09:05:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"73627023-28fb-4907-9a73-4de34937c01f","date":"2024-04-09T08:33:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"62decc0e-6581-401a-952d-67591a1c8025","date":"2024-04-09T07:24:24+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-04-08T19:29:54+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-03-22T20:29:53+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-03-21T05:01:04+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-03-21T05:01:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pregnancy and Childbirth","date":"2024-03-14T02:21:56+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"05aab9a2-823b-48f8-b924-88bd5dece16d","owner":[],"postedDate":"March 25th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-04-29T07:50:49+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-25 08:05:29","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4096693","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4096693","identity":"rs-4096693","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}