Shoulder dystocia in babies born to Aboriginal mothers with diabetes: a population-based cohort study, 1998-2015.

BACKGROUND: Australian Aboriginal and Torres Strait Islander women with diabetes in pregnancy (DIP) are more likely to have glycaemic levels above the target range, and their babies are thus at higher risk of excessive fetal growth. Shoulder dystocia, defined by failure of spontaneous birth of fetal shoulder after birth of the head requiring obstetric maneuvers, is an obstetric emergency that is strongly associated with DIP and fetal size. The aim of this study was to investigate the epidemiology of shoulder dystocia in Aboriginal babies born to mothers with DIP. METHODS: Stratifying by Aboriginal status, characteristics of births complicated by shoulder dystocia in women with and without DIP were compared and incidence and time-trends of shoulder dystocia were described. Compliance with guidelines aiming at preventing shoulder dystocia in women with DIP were compared. Post-logistic regression estimation was used to calculate the population attributable fractions (PAFs) for shoulder dystocia associated with DIP and to estimate probabilities of shoulder dystocia in babies born to mothers with DIP at birthweights > 3 kg. RESULTS: Rates of shoulder dystocia from vaginal births in Aboriginal babies born to mothers with DIP were double that of their non-Aboriginal counterparts (6.3% vs 3.2%, p < 0.001), with no improvement over time. Aboriginal mothers with diabetes whose pregnancies were complicated by shoulder dystocia were more likely to have a history of shoulder dystocia (13.1% vs 6.3%, p = 0.032). Rates of guideline-recommended elective caesarean section in pregnancies with diabetes and birthweight > 4.5 kg were lower in the Aboriginal women (28.6% vs 43.1%, p = 0.004). PAFs indicated that 13.4% (95% CI: 9.7%-16.9%) of shoulder dystocia cases in Aboriginal (2.7% (95% CI: 2.1%-3.4%) in non-Aboriginal) women were attributable to DIP. Probability of shoulder dystocia among babies born to Aboriginal mothers with DIP was higher at birthweights > 3 kg. CONCLUSIONS: Aboriginal mothers with DIP had a higher risk of shoulder dystocia and a stronger association between birthweight and shoulder dystocia. Many cases were recurrent. These factors should be considered in clinical practice and when counselling women.

First Nations Peoples' perceptions, knowledge and beliefs regarding stillbirth prevention and bereavement practices: A mixed methods systematic review.

BACKGROUND: First Nations Peoples endure disproportionate rates of stillbirth compared with non-First Nations Peoples. Previous interventions have aimed at reducing stillbirth in First Nations Peoples and providing better bereavement care without necessarily understanding the perceptions, knowledge and beliefs that could influence the design of the intervention and implementation. AIM: The aim of this review was to understand the perceptions, knowledge and beliefs about stillbirth prevention and bereavement of First Nations Peoples from the US, Canada, Aotearoa/New Zealand, and Australia. METHODS: This review was conducted in accordance with the JBI methodology for a convergent integrated mixed method systematic review. This review was overseen by an advisory board of Aboriginal Elders, researchers, and clinicians. A search of eight databases (PubMed, MEDLINE, PsycInfo, CINAHL, Embase, Emcare, Dissertations and Theses and Indigenous Health InfoNet) and grey literature was conducted. All studies were screened, extracted, and appraised for quality by two reviewers and results were categorised, and narratively summarised. RESULTS: Ten studies were included within this review. Their findings were summarised into four categories: safeguarding baby, traditional practices of birthing and grieving, bereavement photography and post-mortem examination. The results indicate a diversity of perceptions, knowledge and beliefs primarily around smoking cessation and bereavement practices after stillbirth. However, there was a paucity of research available. CONCLUSIONS: Further research is needed to understand the perceptions, knowledge and beliefs about stillbirth among First Nations Peoples. Without research within this area, interventions to prevent stillbirth and support bereaved parents and their communities after stillbirth may face barriers to implementation.

Nonchromosomal birth defects and risk of childhood acute leukemia: An assessment in 15 000 leukemia cases and 46 000 controls from the Childhood Cancer and Leukemia International Consortium.

Although recent studies have demonstrated associations between nonchromosomal birth defects and several pediatric cancers, less is known about their role on childhood leukemia susceptibility. Using data from the Childhood Cancer and Leukemia International Consortium, we evaluated associations between nonchromosomal birth defects and childhood leukemia. Pooling consortium data from 18 questionnaire-based and three registry-based case-control studies across 13 countries, we used multivariable logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between a spectrum of birth defects and leukemia. Our analyses included acute lymphoblastic leukemia (ALL, n = 13 115) and acute myeloid leukemia (AML, n = 2120) cases, along with 46 172 controls. We used the false discovery rate to account for multiple comparisons. In the questionnaire-based studies, the prevalence of birth defects was 5% among cases vs 4% in controls, whereas, in the registry-based studies, the prevalence was 11% among cases vs 7% in controls. In pooled adjusted analyses, there were several notable associations, including (1) digestive system defects and ALL (OR = 2.70, 95% CI: 1.46-4.98); (2) congenital anomalies of the heart and circulatory system and AML (OR = 2.86, 95% CI: 1.81-4.52) and (3) nervous system defects and AML (OR = 4.23, 95% CI: 1.50-11.89). Effect sizes were generally larger in registry-based studies. Overall, our results could point to novel genetic and environmental factors associated with birth defects that could also increase leukemia susceptibility. Additionally, differences between questionnaire- and registry-based studies point to the importance of complementary sources of birth defect phenotype data when exploring these associations.

Overweight/obesity and other predictors of gestational diabetes among Aboriginal and non-Aboriginal women in Western Australia.

This population-based study investigated the association of BMI and other predictors with gestational diabetes mellitus (GDM) among Australian Aboriginal and non-Aboriginal mothers. We conducted a state-wide retrospective cohort study that included all singleton births in Western Australia (n = 134,552) between 2012 and 2015 using population health datasets linked by the Western Australian Data Linkage Branch. Associations between GDM and its predictors were estimated as adjusted relative risks (aRRs) from multivariable generalised linear models. Adjusted ratio of relative risks (aRRRs) compared RRs in Aboriginal and non-Aboriginal mothers. Adjusted population attributable fractions estimated the contribution of overweight/obesity to GDM burden, and adjusted predicted probabilities for GDM were plotted against BMI levels. The following predictors had stronger associations with GDM in Aboriginal, compared to non-Aboriginal, mothers: maternal obesity (aRR [95% CI] 3.16 [2.54-3.93]; aRRR 1.57 [1.26-1.94]), previous LGA (aRR 1.70 [1.37-2.12]; aRRR 1.41 [1.13-1.76]) and previous macrosomia (birthweight ≥ 4 kg) (aRR 1.55 [1.24-1.94]; aRRR 1.53 [1.22-1.91]). 46.1% (95% CI: 36.6-54.1) of GDM cases in Aboriginal women (23.3% in non-Aboriginal mothers, 95% CI: 21.6-25.1) were attributed to overweight/obesity. Compared to non-Aboriginal mothers, adjusted GDM probabilities were higher at all BMI levels and showed greater increase with BMI. Overweight/obesity is a key driver of GDM among Aboriginal women. Association between BMI and GDM is stronger in Aboriginal, compared to non-Aboriginal, women especially at higher BMI.

First Nations populations' perceptions, knowledge, attitudes, beliefs, and myths about prevention and bereavement in stillbirth: a mixed methods systematic review protocol.

OBJECTIVE: The objective of this review is to investigate First Nations populations' perceptions, knowledge, attitudes, beliefs, and myths about stillbirth. INTRODUCTION: First Nations populations experience disproportionate rates of stillbirth compared with non-First Nations populations. There has been a surge of interventions aimed at reducing stillbirth and providing better bereavement care, but these are not necessarily appropriate for First Nations populations. As a first step toward developing appropriate interventions for these populations, this review will examine current perceptions, knowledge, attitudes, beliefs, and myths about stillbirth held by First Nations people from the United States, Canada, Aotearoa/New Zealand, and Australia. INCLUSION CRITERIA: The review will consider studies that include individuals of any age (bereaved or non-bereaved) who identify as belonging to First Nations populations. Eligible studies will include the perceptions, knowledge, attitudes, beliefs, and myths about stillbirth among First Nations populations. METHODS: This review will follow the JBI methodology for convergent mixed methods systematic reviews. The review is supported by an advisory panel of Aboriginal elders, lived-experience stillbirth researchers, Aboriginal researchers, and clinicians. PubMed, MEDLINE (Ovid), CINAHL (EBSCOhost), Embase (Ovid), Emcare (Ovid), PsycINFO (EBSCOhost), Indigenous Health InfoNet, Trove, Informit, and ProQuest Dissertations and Theses will be searched for relevant information. Titles and abstracts of potential studies will be screened and examined for eligibility. After critical appraisal, quantitative and qualitative data will be extracted from included studies, with the former "qualitized" and the data undergoing a convergent integrated approach. REVIEW REGISTRATION: PROSPERO CRD42023379627.

The impact of diabetes during pregnancy on neonatal outcomes among the Aboriginal population in Western Australia: a whole-population study.

BACKGROUND: Aboriginal and Torres Strait Islander (hereafter Aboriginal) women have a high prevalence of diabetes in pregnancy (DIP), which includes pre-gestational diabetes mellitus (PGDM) and gestational diabetes mellitus (GDM). We aimed to characterize the impact of DIP in babies born to Aboriginal mothers. METHODS: A retrospective cohort study, using routinely collected linked health data that included all singleton births (N = 510 761) in Western Australia between 1998 and 2015. Stratified by Aboriginal status, generalized linear mixed models quantified the impact of DIP on neonatal outcomes, estimating relative risks (RRs) with 95% CIs. Ratio of RRs (RRRs) examined whether RRs differed between Aboriginal and non-Aboriginal populations. RESULTS: Exposure to DIP increased the risk of adverse outcomes to a greater extent in Aboriginal babies. PGDM heightened the risk of large for gestational age (LGA) (RR: 4.10, 95% CI: 3.56-4.72; RRR: 1.25, 95% CI: 1.09-1.43), macrosomia (RR: 2.03, 95% CI: 1.67-2.48; RRR: 1.39, 95% CI: 1.14-1.69), shoulder dystocia (RR: 4.51, 95% CI: 3.14-6.49; RRR: 2.19, 95% CI: 1.44-3.33) and major congenital anomalies (RR: 2.14, 95% CI: 1.68-2.74; RRR: 1.62, 95% CI: 1.24-2.10). GDM increased the risk of LGA (RR: 2.63, 95% CI: 2.36-2.94; RRR: 2.00, 95% CI: 1.80-2.22), macrosomia (RR: 1.95, 95% CI: 1.72-2.21; RRR: 2.27, 95% CI: 2.01-2.56) and shoulder dystocia (RR: 2.78, 95% CI: 2.12-3.63; RRR: 2.11, 95% CI: 1.61-2.77). Birthweight mediated about half of the DIP effect on shoulder dystocia only in the Aboriginal babies. CONCLUSIONS: DIP differentially increased the risks of fetal overgrowth, shoulder dystocia and congenital anomalies in Aboriginal babies. Improving care for Aboriginal women with diabetes and further research on preventing shoulder dystocia among these women can reduce the disparities.

Perinatal outcomes of Aboriginal women with mental health disorders.

OBJECTIVE: Maternal mental disorders have been associated with adverse perinatal outcomes such as low birthweight and preterm birth, although these links have been examined rarely among Australian Aboriginal populations. We aimed to evaluate the association between maternal mental disorders and adverse perinatal outcomes among Aboriginal births. METHODS: We used whole population-based linked data to conduct a retrospective cohort study (N = 38,592) using all Western Australia singleton Aboriginal births (1990-2015). Maternal mental disorders were identified based on the International Classification of Diseases diagnoses and grouped into six broad diagnostic categories. The perinatal outcomes evaluated were preterm birth, small for gestational age, perinatal death, major congenital anomalies, foetal distress, low birthweight and 5-minute Apgar score. We employed log-binomial/-Poisson models to calculate risk ratios and 95% confidence intervals. RESULTS: After adjustment for sociodemographic factors and pre-existing medical conditions, having a maternal mental disorder in the five years before the birth was associated with adverse perinatal outcomes, with risk ratios (95% confidence intervals) ranging from 1.26 [1.17, 1.36] for foetal distress to 2.00 [1.87, 2.15] for low birthweight. We found similar associations for each maternal mental illness category and neonatal outcomes, with slightly stronger associations when maternal mental illnesses were reported within 1 year rather than 5 years before birth and for substance use disorder. CONCLUSIONS: This large population-based study demonstrated an increased risk of several adverse birth outcomes among Aboriginal women with mental disorders. Holistic perinatal care, treatment and support for women with mental disorders may reduce the burden of adverse birth outcomes.

Early mortality among aboriginal and non-aboriginal women who had a preterm birth in Western Australia: A population-based cohort study.

BACKGROUND: Having a preterm (<37 weeks' gestation) birth may increase a woman's risk of early mortality. Aboriginal and Torres Strait Islander (hereafter Aboriginal) women have higher preterm birth and mortality rates compared with other Australian women. OBJECTIVES: We investigated whether a history of having a preterm birth was associated with early mortality in women and whether these associations differed by Aboriginal status. METHODS: This retrospective cohort study used population-based perinatal records of women who had a singleton birth between 1980 and 2015 in Western Australia linked to Death Registry data until June 2018. The primary and secondary outcomes were all-cause and cause-specific mortality respectively. After stratification by Aboriginal status, rate differences were calculated, and Cox proportional hazard regression was used to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for all-cause and cause-specific mortality. RESULTS: There were 20,244 Aboriginal mothers (1349 deaths) and 457,357 non-Aboriginal mothers (7646 deaths) with 8.6 million person-years of follow-up. The all-cause mortality rates for Aboriginal mothers who had preterm births and term births were 529.5 and 344.0 (rate difference 185.5, 95% CI 135.5, 238.5) per 100,000 person-years respectively. Among non-Aboriginal mothers, the corresponding figures were 125.5 and 88.6 (rate difference 37.0, 95% CI 29.4, 44.9) per 100,000 person-years. The HR for all-cause mortality for Aboriginal and non-Aboriginal mothers associated with preterm birth were 1.48 (95% CI 1.32, 1.66) and 1.35 (95% CI 1.26, 1.44), respectively, compared with term birth. Compared with mothers who had term births, mothers of preterm births had higher relative risks of mortality from diabetes, cardiovascular, digestive and external causes. CONCLUSIONS: Both Aboriginal and non-Aboriginal women who had a preterm birth had a moderately increased risk of mortality up to 38 years after the birth, reinforcing the importance of primary prevention and ongoing screening.

Severe maternal morbidity following stillbirth in Western Australia 2000-2015: a population-based study.

PURPOSE: There is scant literature about the management of stillbirth and the subsequent risk of severe maternal morbidity (SMM). We aimed to assess the risk of SMM associated with stillbirths compared with live births and whether this differed by the presence of maternal comorbidities. METHODS: In this retrospective cohort study, we used a population-based dataset of all stillbirths and live births ≥ 20 weeks' gestation in Western Australia between 2000 and 2015. SMM was identified using a published Australian composite for use with routinely collected hospital morbidity data. Maternal comorbidities were identified in the Hospital Morbidity Data Collection or the Midwives Notification System using a modified Australian chronic disease composite. Multivariable Poisson regression was used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for factors associated with SMM in analyses stratified by the presence of maternal comorbidities. Singleton and multiple pregnancies were examined separately. RESULTS: This study included 458,639 singleton births (2319 stillbirths and 456,320 live births). The adjusted RRs for SMM among stillbirths were 2.30 (95% CI 1.77, 3.00) for those without comorbidities and 4.80 (95% CI 4.11, 5.59) (Interaction P value < 0.0001) for those with comorbidities compared to live births without and with comorbidities, respectively. CONCLUSION: In Western Australia between 2000 and 2015, mothers of stillbirths both with and without any maternal comorbidities had an increased risk of SMM compared with live births. Further investigation into why women who have had a stillbirth without any existing conditions or pregnancy complications develop SMM is warranted.

Infant feeding practices and childhood acute leukemia: Findings from the Childhood Cancer & Leukemia International Consortium.

Increasing evidence suggests that breastfeeding may protect from childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). However, most studies have limited their analyses to any breastfeeding, and only a few data have examined exclusive breastfeeding, or other exposures such as formula milk. We performed pooled analyses and individual participant data metaanalyses of data from 16 studies (N = 17 189 controls; N = 10 782 ALL and N = 1690 AML cases) from the Childhood Leukemia International Consortium (CLIC) to characterize the associations of breastfeeding duration with ALL and AML, as well as exclusive breastfeeding duration and age at introduction to formula with ALL. In unconditional multivariable logistic regression analyses of pooled data, we observed decreased odds of ALL among children breastfed 4 to 6 months (0.88, 95% CI 0.81-0.96) or 7 to 12 months (OR 0.85, 0.79-0.92). We observed a similar inverse association between breastfeeding ≥4 months and AML (0.82, 95% CI 0.71-0.95). Odds of ALL were reduced among children exclusively breastfed 4 to 6 months (OR 0.73, 95% CI 0.63-0.85) or 7 to 12 months (OR 0.70, 95% CI 0.53-0.92). Random effects metaanalyses produced similar estimates, and findings were unchanged in sensitivity analyses adjusted for race/ethnicity or mode of delivery, restricted to children diagnosed ≥1 year of age or diagnosed with B-ALL. Our pooled analyses indicate that longer breastfeeding is associated with decreased odds of ALL and AML. Few risk factors for ALL and AML have been described, therefore our findings highlight the need to promote breastfeeding for leukemia prevention.

Patterns of recurrent preterm birth in Western Australia: A 36-year state-wide population-based study.

BACKGROUND: It is known that a previous preterm birth increases the risk of a subsequent preterm birth, but a limited number of studies have examined this beyond two consecutive pregnancies. AIMS: This study aimed to assess the risk and patterns of (recurrent) preterm birth up to the fourth pregnancy. MATERIALS AND METHODS: We used Western Australian routinely linked population health datasets to identify women who had two or more consecutive singleton births (≥20 weeks gestation) from 1980 to 2015. A log-binomial model was used to calculate risk ratios (RRs) and 95% confidence interval (CIs) for preterm birth risk in the third and fourth deliveries by the combined outcomes of previous pregnancies. RESULTS: We analysed 255 435 women with 651 726 births. About 7% of women had a preterm birth in the first delivery, and the rate of continuous preterm birth recurrence was 22.9% (second), 44.9% (third) and 58.5% (fourth) deliveries. The risk of preterm birth at the third delivery was highest for women with two prior indicated preterm births (RR 12.5, 95% CI: 11.3, 13.9) and for those whose first pregnancy was 32-36 weeks gestation, and second pregnancy was less than 32 weeks gestation (RR 11.8, 95% CI: 10.3, 13.5). There were similar findings for the second and fourth deliveries. CONCLUSIONS: Our findings demonstrate that women with any prior preterm birth were at greater risk of preterm birth in subsequent pregnancies compared with women with only term births, and the risk increased with shorter gestational length, and the number of previous preterm deliveries, especially sequential ones.

Caesarean section following antepartum stillbirth in Western Australia 2010-2015: A population-based study.

BACKGROUND: There is scant literature about antepartum stillbirth management but guidelines usually recommend reserving caesarean sections for exceptional circumstances. However, little is known about caesarean section rates following antepartum stillbirth in Australia. AIMS: We aimed to describe the onset of labour, mode of birth, and use of analgesia and anaesthesia following antepartum stillbirth and to identify factors associated with caesarean section. MATERIAL AND METHODS: In this retrospective cohort study, we used a population-based dataset of all singleton antepartum stillbirths ≥20 weeks gestation in Western Australia between 2010-2015. The overall, primary and repeat caesarean section rates for antepartum stillbirths were calculated and multivariable Poisson regression analyses were performed to identify associated factors, and to calculate relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: This study included 634 antepartum stillbirths. Labour was spontaneous for 134 (21.1%), induced for 457 (72.1%), and 43 (6.8%) had a prelabour caesarean section. The overall, primary and repeat caesarean section rates were 8.5%, 4.6% and 23.0% respectively and increased with gestation (P trends all <0.01). Other factors associated with an increased caesarean section risk included: any placenta praevia or placental abruption, birth at a metropolitan private hospital, large-for-gestational-age birthweight, and any maternal chronic condition. During labour, the most frequently used types of analgesia were systemic narcotics (46.0%) and regional blocks (34.7%) while among those who had a caesarean section, 40.7% had a general anaesthetic. CONCLUSIONS: In Western Australia between 2010-2015, the caesarean section rates among women with antepartum stillbirths were low, in line with current guidelines.

Trends and burden of diabetes in pregnancy among Aboriginal and non-Aboriginal mothers in Western Australia, 1998-2015.

BACKGROUND: Diabetes in pregnancy (DIP), which includes pre-gestational and gestational diabetes, is more prevalent among Aboriginal women. DIP and its adverse neonatal outcomes are associated with diabetes and cardiovascular disease in the offspring. This study investigated the impact of DIP on trends of large for gestational age (LGA) in Aboriginal and non-Aboriginal populations, and added to the limited evidence on temporal trends of DIP burden in these populations. METHODS: We conducted a retrospective cohort study that included all births in Western Australia between 1998 and 2015 using linked population health datasets. Time trends of age-standardised and crude rates of pre-gestational and gestational diabetes were estimated in Aboriginal and non-Aboriginal mothers. Mixed-effects multivariable logistic regression was used to estimate the association between DIP and population LGA trends over time. RESULTS: Over the study period, there were 526,319 births in Western Australia, of which 6.4% were to Aboriginal mothers. The age-standardised annual rates of pre-gestational diabetes among Aboriginal mothers rose from 4.3% in 1998 to 5.4% in 2015 and remained below 1% in non-Aboriginal women. The comparable rates for gestational diabetes increased from 6.7 to 11.5% over the study period in Aboriginal women, and from 3.5 to 10.2% among non-Aboriginal mothers. LGA rates in Aboriginal babies remained high with inconsistent and no improvement in pregnancies complicated by gestational diabetes and pre-gestational diabetes, respectively. Regression analyses showed that DIP explained a large part of the increasing LGA rates over time in Aboriginal babies. CONCLUSIONS: There has been a substantial increase in the burden of pre-gestational diabetes (Aboriginal women) and gestational diabetes (Aboriginal and non-Aboriginal) in recent decades. DIP appears to substantially contribute to increasing trends in LGA among Aboriginal babies.

Disparities in severe neonatal morbidity and mortality between Aboriginal and non-Aboriginal births in Western Australia: a decomposition analysis.

BACKGROUND: The health disadvantages faced by Australian Aboriginal peoples are evidenced in early life, although few studies have focused on the reasons for population-level inequalities in more severe adverse outcomes. This study aimed to examine the scale of disparity in severe neonatal morbidity (SNM) and mortality between Aboriginal and non-Aboriginal births and quantify the relative contributions of important maternal and infant factors. METHOD: A retrospective cohort study with singleton live births (≥32 weeks' gestation) was conducted using Western Australia linked whole population datasets, from 1999 to 2015. Aboriginal status was determined based on the mothers' self-reported ethnic origin. An Australian validated indicator was adapted to identify neonates with SNM. The Oaxaca-Blinder method was employed to calculate the contribution of each maternal and infant factor to the disparity in SNM and mortality. RESULTS: Analyses included 425 070 births, with 15 967 (3.8%) SNM and mortality cases. The disparity in SNM and mortality between Aboriginal and non-Aboriginal births was 2.9 percentage points (95% CI 2.6 to 3.2). About 71% of this gap was explained by differences in modelled factors including maternal area of residence (23.8%), gestational age (22.2%), maternal age (7.5%) and antenatal smoking (7.2%). CONCLUSIONS: There is a considerable disparity in SNM and mortality between Aboriginal and non-Aboriginal births in Western Australia with the majority of this related to differences in maternal sociodemographic factors, antenatal smoking and gestational age. Public health programmes targeting these factors may contribute to a reduction in early life health differentials and benefit Aboriginal population health through the life course.

Comparison of stillbirth trends over two decades in Wales, United Kingdom and Western Australia: An international retrospective cohort study.

BACKGROUND: Stillbirth is a critical public health issue worldwide. While the rates in high-income countries are relatively low, there are persistent between-country disparities. OBJECTIVES: To compare stillbirth rates and trends in Wales and the State of Western Australia (WA), Australia, and provide insights into any differences. METHODS: In this international retrospective cohort study, we pooled population-based data collections of all births ≥24 weeks' gestation (excluding terminations for congenital anomalies) between 1993 and 2015, divided into six time periods. The stillbirth rate per 1000 births was estimated for each cohort in each time period. Multivariable Poisson regression analyses, adjusted for appropriateness of growth, socio-economic status, maternal age, and multiple birth, were performed to evaluate the interaction between cohort and time period. Relative risk (RR) and 95% confidence interval (CI) for each time period and cohort were calculated. RESULTS: There were 767 731 births (3725 stillbirths) in Wales and 648 373 (2431 stillbirths) in WA. The overall stillbirth rate declined by 15.9% over the study period in Wales (from 5.3 in 1993-96 to 4.5 per 1000 births in 2013-15; Ptrend  < .01) but by 40.4% in WA (from 4.9 to 2.9 per 1000 births in WA; Ptrend  < .01). Using 1993-96 in WA as the reference group, the adjusted RRs for stillbirths at 37-38 weeks' gestation in the most recent study period (2013-15) were 0.85 (95% CI 0.64, 1.13) in Wales and 0.51 (95% CI 0.36, 0.73) in WA. CONCLUSIONS: The stillbirth rates between Wales and WA have widened in the last two decades (especially among late-term births), although the absolute rates for both are distinctly higher than the best-performing nations. While the differences may be partly explained by timing of birth and maternal life style behaviours such as smoking, it is important to identify and ameliorate the associated risk factors to support a reduction in preventable stillbirths.

The impact of maternal prenatal mental health disorders on stillbirth and infant mortality: a systematic review and meta-analysis.

Evidence about the association between maternal mental health disorders and stillbirth and infant mortality is limited and conflicting. We aimed to examine whether maternal prenatal mental health disorders are associated with stillbirth and/or infant mortality. MEDLINE, Embase, PsycINFO, and Scopus were searched for studies examining the association of any maternal prenatal (occurring before or during pregnancy) mental health disorder(s) and stillbirth or infant mortality. A random-effects meta-analysis was used to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs). The between-study heterogeneity was quantified using the I2 statistic. Subgroup analyses were performed to identify the source of heterogeneity. Of 4487 records identified, 28 met our inclusion criteria with 27 contributing to the meta-analyses. Over 60% of studies examined stillbirth and 54% of them evaluated neonatal or infant mortality. Thirteen studies investigated the association between maternal depression and anxiety and stillbirth/infant mortality, pooled OR, 1.42 (95% CI, 1.16-1.73; I2, 76.7%). Another 13 studies evaluated the association between severe maternal mental illness and stillbirth/infant mortality, pooled OR, 1.47 (95% CI, 1.28-1.68; I2, 62.3%). We found similar results for the association of any maternal mental health disorders and stillbirth/infant mortality (OR, 1.59; 95% CI, 1.43-1.77) and in subgroup analyses according to types of fetal/infant mortality. We found no significant evidence of publication bias. Maternal prenatal mental health disorders appear to be associated with a moderate increase in the risk of stillbirth and infant mortality, although the mechanisms are unclear. Efforts to prevent and treat these disorders may reduce the scale of stillbirth/infant deaths.

Socioethnic disparities in severe maternal morbidity in Western Australia: a statewide retrospective cohort study.

OBJECTIVES: To assess the scale of ethnic inequalities in severe maternal morbidity (SMM) rates and quantify the contribution of maternal characteristics to these disparities. DESIGN: Retrospective cohort study. SETTING: Whole-of-population linked administrative data from 2002 to 2015 in Western Australia. PARTICIPANTS: Women with 410 043 birth events (includes all births from the same pregnancy) of 20 weeks' or more gestation, including terminations for congenital anomalies. PRIMARY AND SECONDARY OUTCOME MEASURES: Women with SMM were identified based on a composite indicator of SMM using diagnosis and procedure codes developed for use in routinely collected data. Mothers were classified into seven ethnic groups, based on their reported ethnic origin. The associations between maternal ethnic origin and SMM were examined using a log-binomial model, which estimates risk ratios (RRs) and 95% CIs. The Blinder-Oaxaca decomposition technique was employed to partition the disparity in SMM between Aboriginal and Caucasian populations into 'explained' and 'unexplained' components. RESULTS: During the study period, 9378 SMM cases were documented. In the adjusted model, Aboriginal (RR 1.73, 95% CI 1.59 to 1.87), African (RR 1.64, 95% CI 1.43 to 1.89) and 'other' ethnicity (RR 1.49, 95% CI 1.37 to 1.63) women were at significantly higher risk of SMM compared with Caucasian women. Teenage and older mothers and socioeconomically disadvantaged women were also at greater risk of SMM. Differences in sociodemographic characteristics explained 33.2% of the disparity in SMM between Aboriginal and Caucasian women. CONCLUSIONS: There are distinct disparities in SMM by ethnicity in Western Australia, with a greater risk among Aboriginal and African women. While improvements in SES and a reduction in teenage pregnancy can potentially support a sizeable reduction in SMM rate inequalities, future research should investigate other potential pathways and targeted interventions to close the ethnicity disparity.

Parental occupational exposure to pesticides and risk of childhood cancer in Switzerland: a census-based cohort study.

BACKGROUND: Pesticide exposure is a suspected risk factor for childhood cancer. We investigated the risk of developing childhood cancer in relation to parental occupational exposure to pesticides in Switzerland for the period 1990-2015. METHODS: From a nationwide census-based cohort study in Switzerland, we included children aged < 16 years at national censuses of 1990 and 2000 and followed them until 2015. We extracted parental occupations reported at the census closest to the birth year of the child and estimated exposure to pesticides using a job exposure matrix. Cox proportional hazards models, adjusted for potential confounders, were fitted for the following outcomes: any cancer, leukaemia, central nervous system tumours (CNST), lymphoma, non-CNS solid tumours. RESULTS: Analyses of maternal (paternal) exposure were based on approximately 15.9 (15.1) million-person years at risk and included 1891 (1808) cases of cancer, of which 532 (503) were leukaemia, 348 (337) lymphomas, 423 (399) CNST, and 588 (569) non-CNS solid tumours. The prevalence of high likelihood of exposure was 2.9% for mothers and 6.7% for fathers. No evidence of an association was found with maternal or paternal exposure for any of the outcomes, except for "non-CNS solid tumours" (High versus None; Father: adjusted HR [95%CI] =1.84 [1.31-2.58]; Mother: 1.79 [1.13-2.84]). No evidence of an association was found for main subtypes of leukaemia and lymphoma. A post-hoc analysis on frequent subtypes of "non-CNS solid tumours" showed positive associations with wide CIs for some cancers. CONCLUSION: Our study suggests an increased risk for solid tumours other than in the CNS among children whose parents were occupationally exposed to pesticides; however, the small numbers of cases limited a closer investigation of cancer subtypes. Better exposure assessment and pooled studies are needed to further explore a possible link between specific childhood cancers types and parental occupational exposure to pesticides.

Correction to: Profile of severely growth-restricted births undelivered at 40 weeks in Western Australia.

Unfortunately, after publication, we found errors in the extraction of data on gestational diabetes and threatened miscarriage.