Educational Outcomes for Children at 7 to 9 Years of Age After Birth at 39 vs 40 to 42 Weeks' Gestation

Importance

Birth at 39 weeks' gestation is common and thought to be safe for mother and neonate. However, findings of long-term outcomes for children born at this gestational age have been conflicting.

Objective

To evaluate the association of birth at 39 weeks' gestation with childhood numeracy and literacy scores at ages 7 to 9 years compared with birth at 40 to 42 weeks' gestation.

Design, Setting, and Participants

In this Australian statewide, population-based cohort study using a causal inference framework based on target trial emulation, perinatal data on births between January 1, 2005, and December 31, 2011, were linked to educational outcomes at 7 to 9 years of age. Statistical analyses were performed from December 2022 to June 2023.

Exposure

Birth at 39 weeks' gestation compared with birth at 40 to 42 weeks' gestation.

Main Outcomes and Measures

Numeracy and literacy outcomes were assessed at 7 to 9 years of age using Australian National Assessment Program-Literacy and Numeracy data and defined by overall z score across 5 domains (grammar and punctuation, reading, writing, spelling, and numeracy). Multiple imputation and doubly robust inverse probability weighted regression adjustment were used to estimate population average causal effects.

Results

The study population included 155 575 children. Of these children, 49 456 (31.8%; 24 952 boys [50.5%]) were born at 39 weeks' gestation and were compared with 106 119 (68.2%; 52 083 boys [49.1%]) born at 40 to 42 weeks' gestation. Birth at 39 weeks' gestation was not associated with altered educational outcomes for children aged 7 to 9 years compared with their peers born at 40 to 42 weeks' gestation (mean [SE] z score, 0.0008 [0.0019] vs -0.0031 [0.0038]; adjusted risk difference, -0.004 [95% CI, -0.015 to 0.007]). Each educational domain was investigated, and no significant difference was found in grammar and punctuation (risk difference [RD], -0.006 [95% CI, -0.016 to 0.005]), numeracy (RD, -0.009 [95% CI, -0.020 to 0.001]), spelling (RD, 0.001 [95% CI, -0.011 to 0.0013]), reading (RD, -0.008 [95% CI, -0.019 to 0.003]), or writing (RD, 0.006 [95% CI, -0.005 to 0.016]) scores for children born at 39 weeks' gestation compared with those born at 40 to 42 weeks' gestation. Birth at 39 weeks' gestation also did not increase the risk of scoring below national minimum standards in any of the 5 tested domains.

Conclusions and Relevance

Using data from a statewide linkage study to emulate the results of a target randomized clinical trial, this study suggests that there is no evidence of an association of birth at 39 weeks' gestation with numeracy and literacy outcomes for children aged 7 to 9 years.

Perinatal outcomes of socially disadvantaged women in Australia: A population-based retrospective cohort study

OBJECTIVE

To examine the perinatal outcomes of women who experience social disadvantage using population-based perinatal data collected between 1999 and 2016.

DESIGN

Population-based, retrospective cohort study.

SETTING

Victoria, Australia.

POPULATION OR SAMPLE

A total of 1 188 872 singleton births were included.

METHODS

Cohort study using routinely collected perinatal data. Multiple logistic regression was performed to determine associations between social disadvantage and adverse maternal and neonatal outcomes with confidence limits set at 99%. Time-trend analysis for perinatal outcomes was performed in relation to area-level disadvantage measures.

MAIN OUTCOME MEASURES

Incidence of maternal admission to intensive care unit (ICU), postpartum haemorrhage (PPH) and caesarean section, perinatal mortality, preterm birth, low birthweight (LBW), and admission to special care nursery/neonatal intensive care unit (SCN/NICU).

RESULTS

Social disadvantage was associated with higher odds of adverse perinatal outcomes. Disadvantaged women were more likely to be admitted to ICU, have a PPH or experience perinatal mortality (stillbirth or neonatal death) and their neonates were more likely to be admitted to SCN/NICU, be born preterm and be LBW. A persistent social gradient existed across time for the most disadvantaged women for all outcomes except caesarean section.

CONCLUSIONS

Social disadvantage has a marked negative impact on perinatal outcomes. This aligns with national and international evidence regarding the impact of disadvantage. Strategies that improve access to, and reduce fragmentation in, maternity care in addition to initiatives that address the social determinants of health may contribute to improving perinatal outcomes for socially disadvantaged women.

Collaborative maternity and newborn dashboard (CoMaND) for the COVID-19 pandemic: a protocol for timely, adaptive monitoring of perinatal outcomes in Melbourne, Australia

BACKGROUND

The COVID-19 pandemic has resulted in a range of unprecedented disruptions to maternity care with documented impacts on perinatal outcomes such as stillbirth and preterm birth. Metropolitan Melbourne has endured one of the longest and most stringent lockdowns in globally. This paper presents the protocol for a multicentre study to monitor perinatal outcomes in Melbourne, Australia, during the COVID-19 pandemic.

METHODS

Multicentre observational study analysing monthly deidentified maternal and newborn outcomes from births >20 weeks at all 12 public maternity services in Melbourne. Data will be merged centrally to analyse outcomes and create run charts according to established methods for detecting non-random 'signals' in healthcare. Perinatal outcomes will include weekly rates of total births, stillbirths, preterm births, neonatal intensive care admissions, low Apgar scores and fetal growth restriction. Maternal outcomes will include weekly rates of: induced labour, caesarean section, births before arrival to hospital, postpartum haemorrhage, length of stay, general anaesthesia for caesarean birth, influenza and COVID-19 vaccination status, and gestation at first antenatal visit. A prepandemic median for all outcomes will be calculated for the period of January 2018 to March 2020. A significant shift is defined as ≥6 consecutive weeks, all above or below the prepandemic median. Additional statistical analyses such as regression, time series and survival analyses will be performed for an in-depth examination of maternal and perinatal outcomes of interests.

ETHICS AND DISSEMINATION

Ethics approval for the collaborative maternity and newborn dashboard project has been obtained from the Austin Health (HREC/64722/Austin-2020) and Mercy Health (ref. 2020-031).

TRIAL REGISTRATION NUMBER

ACTRN12620000878976; Pre-results.

Associations Between Maternal Immunisation and Reduced Rates of Preterm Birth and Stillbirth: A Population Based Retrospective Cohort Study

Stillbirth and preterm birth (PTB) remain two of the most important, unresolved challenges in modern pregnancy care. Approximately 10% of all births are preterm with nearly one million children dying each year due to PTB. It remains the most common cause of death among children under five years of age. The numbers for stillbirth are no less shocking with 2.6 million babies stillborn each year. With minimal impact on the rate of these adverse birth outcomes over the past decade there is an urgent need to identify more effective interventions to tackle these problems. In this retrospective cohort study, we used whole-of-population data, to determine if maternal immunization during pregnancy against influenza and/or pertussis, is associated with a lower risk of PTB, delivering a small-for-gestational age (SGA) infant, developing preeclampsia or stillbirth. Women with a singleton pregnancy at 28 or more weeks' gestation delivering in Victoria, Australia from July 2015 to December 2018 were included in the analysis. Log-binomial regression was used to measure the relationship between vaccination during pregnancy against influenza and against pertussis, with preterm birth, SGA, preeclampsia and stillbirth. Variables included in the adjusted model were maternal age, body mass index, first or subsequent birth, maternal Indigenous status, socio-economic quintile, smoking, public or private maternity care and metropolitan or rural location of the hospital. Women who received influenza vaccine were 75% less likely to have a stillbirth (aRR 025; 95% CI 0.20, 0.31), and 31% less likely to birth <37 weeks (aRR 0.69; 95% CI 0.66, 0.72). Women who received pertussis vaccine were 77% less likely to have a stillbirth (aOR 0.23; 95% CI 0.18, 0.28) and 32% less likely to birth <37 weeks gestation (aRR 0.68; 95% CI 0.66, 0.71). Vaccination also reduced the odds of small for gestational age by 13% and reduced the odds of pre-eclampsia when restricted to primiparous women. This association was seen over four different influenza seasons and independent of the time of year suggesting that any protective effect on obstetric outcomes afforded by maternal vaccination may not be due to a pathogen-specific response but rather due to pathogen-agnostic immune-modulatory effects.

Association Between Iatrogenic Delivery for Suspected Fetal Growth Restriction and Childhood School Outcomes

IMPORTANCE

Timely delivery of infants suspected of having fetal growth restriction (FGR) is a balance between preventing stillbirth and minimizing prematurity, particularly because many infants with suspected FGR have normal growth.

OBJECTIVE

To explore the association between iatrogenic delivery for suspected FGR and childhood school outcomes.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective whole-population cohort study linking perinatal data from births 32 weeks' or more gestation between January 1, 2003, to December 31, 2013, to developmental and educational test scores at preparatory school, and at school grades 3, 5, and 7 in Victoria, Australia. Follow-up was concluded in 2019.

EXPOSURES

Suspicion or nonsuspicion of FGR, presence or absence of iatrogenic delivery (defined as early induction of labor or cesarean delivery prior to labor) for suspected FGR, and presence or absence of small for gestational age (SGA).

MAIN OUTCOMES AND MEASURES

The coprimary outcomes were being in the bottom 10th percentile on 2 or more of 5 developmental domains at school entry and being below the national minimum standard on 2 or more of 5 educational domains in grades 3, 5, or 7.

RESULTS

In the birth population of 705 937 infants, the mean gestation at birth was 39.1 (SD, 1.5) weeks and the mean birth weight was 3426 (SD, 517) grams. The birth population linked to 181 902 children with developmental results and 425 717 children with educational results. Compared with infants with severe SGA (birth weight <3rd percentile) not suspected of having FGR, infants with severe SGA delivered for suspected FGR were born earlier (mean gestation, 37.9 weeks vs 39.4 weeks). They also had a significantly increased risk of poor developmental outcome at school entry (16.2% vs 12.7%; absolute difference, 3.5% [95% CI, 0.5%-6.5%]); adjusted odds ratio [aOR], 1.36 [95% CI, 1.07-1.74]) and poor educational outcomes in grades 3, 5, and 7 (for example, in grade 7: 13.4% vs 10.5%; absolute difference, 2.9% [95% CI, 0.4%-5.5%]); aOR, 1.33 [95% CI, 1.04-1.70]). There was no significant difference between infants with normal growth (birth weight ≥10th percentile) delivered for suspected FGR and those not suspected of having FGR in developmental outcome (8.6% vs 8.1%; absolute difference, 0.5% [95% CI, -1.1% to 2.0%]); aOR, 1.17 [95% CI, 0.95-1.45]) or educational outcome in grade 3, 5 or 7, despite being born earlier (mean gestation, 38.0 weeks vs 39.1 weeks).

CONCLUSIONS AND RELEVANCE

In this exploratory study conducted in Victoria, Australia, iatrogenic delivery of infants with severe SGA due to suspected FGR was associated with poorer school outcomes compared with infants with severe SGA not suspected of having FGR. Iatrogenic delivery of infants with normal growth due to suspected FGR was not associated with poorer school outcomes compared with infants with normal growth not suspected of having FGR.

Risk of major labour-related complications for pregnancies progressing to 42 weeks or beyond

BACKGROUND

Post-term gestation beyond 41⁺⁶ completed weeks of gestation is known to be associated with a sharp increase in the risk of stillbirth and perinatal mortality. However, the risk of common adverse outcomes related to labour, such as shoulder dystocia and post-partum haemorrhage for those delivering at this advanced gestation, remains poorly characterised. The objective of this study was to examine the risk of adverse, labour-related outcomes for women progressing to 42 weeks gestation or beyond, compared with those giving birth at 39 completed weeks.

METHODS

We performed a state-wide cohort study using routinely collected perinatal data in Australia. Comparing the two gestation cohorts, we examined the adjusted relative risk of clinically significant labour-related adverse outcomes, including macrosomia (≥ 4500 at birth), post-partum haemorrhage (≥1000 ml), shoulder dystocia, 3rd or 4th degree perineal tear and unplanned caesarean section. Parity, maternal age and mode of birth were adjusted for using logistic regression.

RESULTS

The study cohort included 91,314 women who birthed at 39 completed weeks and 4317 at ≥42 completed weeks. Compared to 39 weeks gestation, those giving birth ≥42 weeks gestation had an adjusted relative risk (aRR) of 1.85 (95% CI 1.55-2.20) for post-partum haemorrhage following vaginal birth, 2.29 (95% CI 1.89-2.78) following instrumental birth and 1.44 (95% CI 1.17-1.78) following emergency caesarean section; 1.43 (95% CI 1.16-1.77) for shoulder dystocia (for non-macrosomic babies); and 1.22 (95% CI 1.03-1.45) for 3rd or 4th degree perineal tear (all women). The adjusted relative risk of giving birth to a macrosomic baby was 10.19 (95% CI 8.26-12.57) among nulliparous women and 4.71 (95% CI 3.90-5.68) among multiparous women. The risk of unplanned caesarean section was 1.96 (95% CI 1.86-2.06) following any labour and 1.47 (95% CI 1.38-1.56) following induction of labour.

CONCLUSIONS

Giving birth at ≥42 weeks gestation may be an under-recognised risk factor for several important, labour-related adverse outcomes. Clinicians should be aware that labour at this advanced gestation incurs a higher risk of adverse outcomes. In addition to known perinatal risks, the risk of obstetric complications should be considered in the counselling of women labouring at post-term gestation.

Validation of anaemia, haemorrhage and blood disorder reporting in hospital data in New South Wales, Australia

OBJECTIVE

Hospital data are a useful resource for studying pregnancy complications, including bleeding-related conditions, however, the reliability of these data is unclear. This study aims to examine reliability of reporting of bleeding-related conditions, including anaemia, obstetric haemorrhage and blood disorders, and procedures, such as blood transfusion and hysterectomy, in coded hospital records compared with obstetric data from two large tertiary hospitals in New South Wales.

RESULTS

There were 36,051 births between 2011 and 2015 included in the analysis. Anaemia and blood disorders were poorly reported in the hospital data, with sensitivity ranging from 2.5% to 24.8% (positive predictive value (PPV) 12.0-82.6%). Reporting of postpartum haemorrhage, transfusion and hysterectomy showed high sensitivity (82.8-96.0%, PPV 78.0-89.6%) while moderate consistency with the obstetric data was observed for other types of obstetric haemorrhage (sensitivity: 41.9-65.1%, PPV: 50.0-56.8%) and placental complications (sensitivity: 68.2-81.3%, PPV: 20.3-72.3%). Our findings suggest that hospital data may be a reliable source of information on postpartum haemorrhage, transfusion and hysterectomy. However, they highlight the need for caution for studies of anaemia and blood disorders, given high rates of uncoded and 'false' cases, and suggest that other sources of data should be sought where possible.

Trends in singleton preterm birth in Victoria, 2007 to 2017: A consecutive cross-sectional study

Introduction

Preterm birth is a major cause of perinatal morbidity and mortality worldwide. In many countries preterm birth rates are increasing, largely as a result of increases in iatrogenic preterm birth, whereas in other countries rates are stable or even declining. The objective of the study is to describe trends in singleton preterm births in Victoria from 2007 to 2017 in relation to trends in perinatal mortality to identify opportunities for improvements in clinical care.

Material and methods

We conducted a consecutive cross‐sectional study in all women with a singleton pregnancy giving birth at ≥20 weeks of pregnancy in Victoria, Australia, between 2007 and 2017, inclusive. Rates of preterm birth and perinatal mortality were calculated and trends were analyzed in all pregnancies, in pregnancies complicated by fetal growth problems, hypertension, (pre)eclampsia or prelabor rupture of membranes (PROM), and in (low‐risk) pregnancies not complicated by any of these conditions.

Results

There were 811 534 singleton births between 2007 and 2017. Preterm birth increased from 5.9% (4074 births) to 6.4% (4893 births; P < .001), due to an increase in iatrogenic preterm birth from 2.5% (1730 births) to 3.6% (2730 births; P < .001). Comparable trends were seen in pregnancies complicated by fetal growth problems and hypertension and in pregnancies not complicated by small for gestational age (SGA), hypertension, (pre)eclampsia or PROM (all P < .001). In pregnancies complicated by SGA, hypertension, (pre)eclampsia or PROM the perinatal mortality rate from 20 weeks of gestation fell (13 to 12 per 1000 births; P < .001). In pregnancies not complicated by SGA, hypertension, (pre)eclampsia or PROM there was no significant change in the perinatal mortality from 28 weeks and no decrease in the preterm weekly prospective stillbirth risk.

Conclusions

The singleton preterm birth rate in Victoria is increasing, driven by an increase in iatrogenic preterm birth, both in pregnancies complicated by SGA and hypertension, and in pregnancies not complicated by SGA, hypertension, (pre)eclampsia or PROM. While perinatal mortality decreased in the pregnancies complicated by SGA, hypertension, (pre)eclampsia or PROM, no significant reduction in perinatal mortality from 28 weeks or in preterm weekly prospective stillbirth risk was noted in the pregnancies not complicated by any of these conditions.

Adverse birth outcomes in Victoria, Australia in association with maternal exposure to low levels of ambient air pollution

BACKGROUND

The relationship between maternal exposure to air pollution and birth outcomes is not well characterised where ambient air pollution is relatively low.

OBJECTIVES

We aimed to explore the association between maternal exposure to ambient nitrogen dioxide (NO₂) and fine particulate matter (PM_2.5) and a range of birth outcomes in Victoria, Australia. Secondary aims were to explore whether obstetric conditions, such as gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy, were effect modifiers in observed relationships.

METHODS

We included all singleton births occurring in Victoria, Australia from 1^st March 2012 to 31^st December 2015 using routinely collected government data. Outcomes included birth weight, small for gestational age (SGA), term low birth weight (tLBW), large for gestational age (LGA), and spontaneous preterm birth (sPTB). We estimated exposure to annual ambient NO₂ and PM_2.5 concentrations, assigned to maternal residence at time of birth. Confounders included maternal, meteorological and temporal variables. Multivariable linear regression and log-binomial regression were used for continuous and dichotomous outcomes, respectively.

RESULTS

There were 285,594 births during the study period. Average NO₂ exposure was 6.0 parts per billion (ppb, median 5.6; interquartile range (IQR) 3.9) and PM_2.5 was 6.9 μg/m³ (median 7.1, IQR 1.3). IQR increases in ambient NO₂ and PM_2.5 were associated with fetal growth restriction, including decrements in birth weight (NO₂ β -22.8 g; 95%CI -26.0, -19.7; PM_2.5 β -14.8 g; 95%CI -17.4, -12.2) and increased risk of SGA (NO₂ RR 1.08; 95%CI 1.06, 1.10; PM_2.5 RR 1.05; 95%CI 1.04, 1.07) and tLBW (NO₂ RR 1.06; 95%CI 1.01, 1.10; PM_2.5 RR 1.04; 95%CI 1.03, 1.08). Women with GDM and hypertensive disorders of pregnancy had greater decrements in birth weight in association with pollutant exposure.

DISCUSSION

In this exploratory study using an annual metric of exposure, maternal exposure to low-level ambient air pollution was associated with fetal growth restriction, which carries substantial public health implications.

Maternal Exposure to Ambient Air Pollution and Pregnancy Complications in Victoria, Australia

The relationship between maternal exposure to ambient air pollution and pregnancy complications is not well characterized. We aimed to explore the relationship between maternal exposure to ambient nitrogen dioxide (NO₂) and fine particulate matter (PM_2.5) and hypertensive disorders of pregnancy, gestational diabetes mellitus (GDM) and placental abruption. Using administrative data, we defined a state-wide cohort of singleton pregnancies born between 1 March 2012 and 31 December 2015 in Victoria, Australia. Annual average NO₂ and PM_2.5 was assigned to maternal residence at the time of birth. 285,594 singleton pregnancies were included. An IQR increase in NO₂ (3.9 ppb) was associated with reduced likelihood of hypertensive disorders of pregnancy (RR 0.89; 95%CI 0.86, 0.91), GDM (RR 0.92; 95%CI 0.90, 0.94) and placental abruption (RR 0.81; 95%CI 0.69, 0.95). Mixed observations and smaller effect sizes were observed for IQR increases in PM_2.5 (1.3 µg/m³) and pregnancy complications; reduced likelihood of hypertensive disorders of pregnancy (RR 0.95; 95%CI 0.93, 0.97), increased likelihood of GDM (RR 1.02; 95%CI 1.00, 1.03) and no relationship for placental abruption. In this exploratory study using an annual metric of exposure, findings were largely inconsistent with a priori expectations and further research involving temporally resolved exposure estimates are required.

Male-biased sex ratios in Australian migrant populations: a population-based study of 1 191 250 births 1999-2015

Background

The naturally occurring male-to-female (M/F) ratio at birth is 1.05. Higher ratios found primarily in countries across Asia have been attributed to prenatal sex selection due to son preference. There is growing evidence that sex-selective practices continue following migration; however, little is known about these practices following migration to Australia.

Methods

In this population-based study we assessed M/F ratios at birth per mother’s country of birth for all registered births 1999–2015 in Victoria, Australia (n = 1 191 250). We also compared the M/F ratio among births to mothers born elsewhere to that of mothers born in Australia, stratified by time period and parity.

Results

Compared with the naturally occurring M/F ratio as well as to the M/F ratio among births to mothers born in Australia, there was an increased ratio of male births to mothers born in India, China and South-East Asia, particularly at higher parities and in more recent time periods (elevated M/F ratios ranged from 1·079 to 1·248, relative risks of male birth ranged from 1·012 to 1·084 with confidence intervals between 1·001 and 1·160 and P-values between 0·005 and 0·039). The most male-biased sex ratios were found among multiple births to Indian-born mothers, and parity of two or more births to Indian and Chinese-born mothers in 2011–15.

Conclusions

The male-biased sex ratios observed in this study indicate that prenatal sex selection may be continuing following migration to Australia from countries where these practices have been documented. The excess of males among multiple births raises the question as to what role assisted reproduction plays. Findings also suggest that systematic discrimination against females starts in the womb.

Planned private homebirth in Victoria 2000-2015: a retrospective cohort study of Victorian perinatal data

BACKGROUND

The outcomes for planned homebirth in Victoria are unknown. We aimed to compare the rates of outcomes for high risk and low risk women who planned to birth at home compared to those who planned to birth in hospital.

METHODS

We undertook a population based cohort study of all births in Victoria, Australia 2000-2015. Women were defined as being of low or high risk of adverse pregnancy outcomes according to the eligibility criteria for homebirth and either planning to birth at home or in a hospital setting at the at the onset of labour. Rates of perinatal and maternal mortality and morbidity as well as obstetric interventions were compared.

RESULTS

Three thousand nine hundred forty-five women planned to give birth at home with a privately practising midwife and 829,286 women planned to give birth in a hospital setting. Regardless of risk status, planned homebirth was associated with significantly lower rates of all obstetric interventions and higher rates of spontaneous vaginal birth (p ≤ 0.0001 for all). For low risk women the rates of perinatal mortality were similar (1.6 per 1000 v's 1.7 per 1000; p = 0.90) and overall composite perinatal (3.6% v's 13.4%; p ≤ 0.001) and maternal morbidities (10.7% v's 17.3%; p ≤ 0.001) were significantly lower for those planning a homebirth. Planned homebirth among high risk women was associated with significantly higher rates of perinatal mortality (9.3 per 1000 v's 3.5 per 1000; p = 0.009) but an overall significant decrease in composite perinatal (7.8% v's 16.9%; p ≤ 0.001) and maternal morbidities (16.7% v's 24.6%; p ≤ 0.001).

CONCLUSION

Regardless of risk status, planned homebirth was associated with significantly lower rates of obstetric interventions and combined overall maternal and perinatal morbidities. For low risk women, planned homebirth was also associated with similar risks of perinatal mortality, however for women with recognized risk factors, planned homebirth was associated with significantly higher rates of perinatal mortality.

Maternal region of birth and stillbirth in Victoria, Australia 2000-2011: A retrospective cohort study of Victorian perinatal data

BACKGROUND

There is growing evidence from high-income countries that maternal country of birth is a risk factor for stillbirth. We aimed to examine the association between maternal region of birth and stillbirth between 2000 and 2011 inclusive in Victoria, Australia.

METHODS

Retrospective population based cohort study of all singleton births at 24 or more weeks gestational age from 2000-2011 in Victoria, Australia. Stillbirths due to termination of pregnancy, babies with congenital anomalies and Indigenous mothers were excluded. Main Outcome Measure: Stillbirth.

RESULTS

Over the 12-year period there were 685,869 singleton births and 2299 stillbirths, giving an overall stillbirth rate of 3·4 per 1000 births. After adjustment for risk factors, compared to women born in Australia/New Zealand, women born in South Asia (aOR 1.27, 95% CI 1.01-1.53, p = 0.01), were more likely to have a stillbirth whereas women born in South East and East Asia were (aOR 0.60, (95% CI 0.49-0.72, p<0.001) less likely to have a stillbirth. Additionally, the increasing rate of stillbirth as gestation length progressed began to rise earlier and more steeply in the South Asian compared to Australian/New Zealand born women. The following risk factors were also significantly associated with an increased odds of stillbirth in multivariate analyses: maternal age <20 and 35 years and more, nulliparity, low socio-economic status, previous stillbirth, no ultrasound reported in 1st trimester, pre-existing hypertension, antepartum haemorrhage and failure to detect growth restriction antenatally.

CONCLUSION

Maternal region of birth is an independent risk factor for stillbirth. Improvements in the rate of stillbirth, particularly late pregnancy stillbirth, are likely to be gained in high-income settings where clinical care is informed by maternal region of birth.