Contrasting socioeconomic inequality with noncommunicable diseases: Insights from a population-based survey using the concentration index in Kong cohort study

Background

Noncommunicable diseases (NCDs) are the major causes of mortality across the globe, which impose a substantial burden on health care systems, particularly in low- and middle-income countries. The present study aimed to determine socioeconomic inequality in the prevalence of NCDs using the concentration index (CI).

Methods

This cross-sectional study was conducted on the baseline data of the Bandar Kong cohort. The principal component analysis was used to determine people's socioeconomic status (SES). The CI and Lorenz Curve were used for the assessment of socioeconomic inequality. Multivariate logistic regression was used to assess the relationship between SES and the prevalence of NCDs. A p Value less than 0.05 is considered significant.

Results

Frequency and prevalence of diabetes was 653 (16.22%), hypertension 848 (21.06%), chronic lung diseases 161 (4%), epilepsy 70 (1.74%), mental disorders 191 (4.74%), stillbirth 299 (13.94%), thyroid disorders 391 (9.71%) and depression 146 (3.63%). CI for the prevalence of diabetes was [-0.107, %95 CI: -0.146 to -0.068], hypertension [-0.122, %95 CI: -0.155 to -0.088], chronic lung disease [-0.116, %95 CI: -0.202 to -0.03], psychiatric disorders [-0.230, %95 CI: -0.304 to -0.155], depression [-0.132, %95 CI: -0.220 to-0.043] and stillbirth [-0.162, %95 CI: -0.220 to -0.105]. The Gini index was negative for all these diseases, indicating that these are significantly concentrated in people of poor SES.

Conclusions

The findings suggest that selected NCDs were concentrated among the poor and the low-income. Particular attention may be necessary to address the problem of NCDs among these groups.

Maternal characteristics as indications for routine induction of labor: A nationwide retrospective cohort study

BACKGROUND

Maternal characteristics, such as parity and age, are increasingly considered indications for routine induction of labor of otherwise healthy women to prevent fetal and neonatal mortality. To fully balance the risks and benefits of induction of labor, we examined the association of additional relevant maternal characteristics and gestational age with fetal and neonatal mortality.

METHODS

We conducted a nationwide retrospective cohort study among a healthy Dutch population consisting of all singleton pregnancies in midwife-led care after 37 weeks of gestation in the period 2000-2018. We examined the association of maternal ethnicity, age, parity, and socioeconomic status with fetal and neonatal mortality, stratified by gestational age. The association of single characteristics was examined using descriptive statistics, and univariable and multivariable logistics regression analyses. The associations of multiple characteristics were examined using inter-categorical analyses and using interaction terms in the multivariable logistic regression analyses.

RESULTS

The results showed that ethnicity, age, parity, socioeconomic status, and gestational age did not act as single determinant of fetal and neonatal mortality. The probability of fetal and neonatal mortality differed among subgroups of women depending on which determinants were considered and the number of determinants included.

CONCLUSIONS

Decision-making about induction of labor to prevent fetal and neonatal mortality based on a single determinant may lead to overuse or underuse of IOL. A value-based health care strategy, addressing social inequity, and investing in better screening and diagnostic methods that employ an individualized and multi-determinant approach may be more effective at preventing fetal and neonatal mortality.

Social inequalities in the provision of obstetric services in Norway 1967-2009: a population-based cohort study

Background

Socioeconomic (SE) inequalities have been observed in a number of adverse outcomes of pregnancy and many of the risk factors for such outcomes are associated with a low SE level. However, SE inequalities persist even after adjustment for these risk factors. Less well-off women are more vulnerable, but may also get less adequate health services. The objective of the present study was to assess possible associations between SE conditions in terms of maternal education as well as ethnic background and obstetric care.

Methods

A population-based national cohort study from the Medical Birth Registry of Norway. The study population comprised 2 305 780 births from the observation period 1967–2009. Multilevel analysis was used because of the hierarchical structure of the data. Outcome variables included induction of labour, epidural analgesia, caesarean section, neonatal intensive care and perinatal death.

Results

While medical interventions in the 1970s were employed less frequently in women of short education and non-western immigrants, this difference was eliminated or even reversed towards the end of the observation period. However, an excess perinatal mortality in both the short-educated [adjusted relative risk (aRR) = 2.49] and the non-western immigrant groups (aRR = 1.75) remained and may indicate increasing health problems in these groups.

Conclusion

Even though our study suggests a fair and favourable development during the last decades in the distribution across SE groups of obstetric health services, the results suggest that the needs for obstetric care have increased in vulnerable groups, requiring a closer follow-up.

Understanding high rates of stillbirth and neonatal death in a disadvantaged, high-migrant district in France: A perinatal audit

INTRODUCTION

The objective of this study is to investigate factors associated with risks of perinatal death in a disadvantaged, high-migrant French district with mortality rates above the national average.

MATERIAL AND METHODS

The study design is a perinatal audit in 2014 in all 11 maternity units in the Seine-Saint-Denis district (25 037 births). The data come from medical chart abstraction, maternal interviews and peer assessor confidential review of deaths. A representative sample of live births in the same district, from the 2010 French Perinatal Survey, was used for comparisons (n = 429). The main outcome measures were stillbirth and neonatal death (0-27 days) at ≥22 weeks of gestation.

RESULTS

The audit included 218 women and 227 deaths (156 stillbirths, 71 neonatal deaths); 75 women were interviewed. In addition to primiparity and multiple pregnancy, overweight and obesity increased mortality risks (50% of cases, adjusted odds ratios [aOR] 1.7, 95% confidence interval [CI] 1.1-2.8, and aOR 1.9 [95% CI 1.1-3.2], respectively) as did the presence of preexisting medical/obstetric conditions (28.6% of cases, aOR 3.2, 95% CI 2.0-5.3). Problems accessing or complying with care were noted in 25% of medical records and recounted in 50% of interviews. Assessors identified suboptimal factors in 73.2% of deaths and judged 33.9% to be possibly or probably preventable. Care not adapted to risk factors and poor healthcare coordination were frequent suboptimal factors. Possibly preventable deaths were higher (P < .05) for women with gestational diabetes or hypertension (44.6%) than women without (29.0%).

CONCLUSIONS

Preventive actions to improve healthcare referral and coordination, especially for overweight and obese women and women with medical and obstetrical risk factors, could reduce perinatal mortality in disadvantaged areas.

Night work and miscarriage: a Danish nationwide register-based cohort study

Objective

Observational studies indicate an association between working nights and miscarriage, but inaccurate exposure assessment precludes causal inference. Using payroll data with exact and prospective measurement of night work, the objective was to investigate whether working night shifts during pregnancy increases the risk of miscarriage.

Methods

A cohort of 22 744 pregnant women was identified by linking the Danish Working Hour Database (DWHD), which holds payroll data on all Danish public hospital employees, with Danish national registers on births and admissions to hospitals (miscarriage). The risk of miscarriage during pregnancy weeks 4–22 according to measures of night work was analysed using Cox regression with time-varying exposure adjusted for a fixed set of potential confounders.

Results

In total 377 896 pregnancy weeks (average 19.7) were available for follow-up. Women who had two or more night shifts the previous week had an increased risk of miscarriage after pregnancy week 8 (HR 1.32 (95% CI 1.07 to 1.62) compared with women, who did not work night shifts. The cumulated number of night shifts during pregnancy weeks 3–21 increased the risk of miscarriages in a dose-dependent pattern.

Conclusions

The study corroborates earlier findings that night work during pregnancy may confer an increased risk of miscarriage and indicates a lowest observed threshold level of two night shifts per week.

Trends of Social Inequalities in the Specific Causes of Infant Mortality in a Nationwide Birth Cohort in Korea, 1995-2009

The relationship between social disparity and specific causes of infant mortality has rarely been studied. The present study analyzed infant mortality trends according to the causes of death and the inequalities in specific causes of infant mortality between different parental social classes. We analyzed 8,209,836 births from the Statistics Korea between 1995 and 2009. The trends of disparity for cause-specific infant mortality according to parental education and employment were examined using the Cox proportional hazard model for the birth-year intervals of 1995-1999, 2000-2004, and 2005-2009. Adjusted hazard ratios were calculated after adjusting for infants' gender, parents' age, maternal obstetrical history, gestational age, and birth weight. An increasing trend in social inequalities in all-cause infant mortality according to paternal education was evident. Social inequalities in infant mortality were greater for "Not classified symptoms, signs and findings" (International Classification of Diseases 10th revision [ICD-10]: R00-R99) and "Injury, poisoning and of external causes" (S00-T98), particularly for "Ill-defined and unspecified causes" (R990) and "Sudden infant death syndrome (SIDS)" (R950); and increased overtime for "Not classified symptoms, signs and findings" (R00-R99), "Injury, poisoning and of external causes" (S00-T98) and "Conditions in perinatal period" (P00-P96), particularly for "SIDS" (R950) and "Respiratory distress syndrome of newborns (RDS)" (P220). The specific causes of infant mortality, in particular the "Not classified causes" (R00-R99 coded deaths) should be investigated more thoroughly to reduce inequality in health.

Understanding determinants of unequal distribution of stillbirth in Tehran, Iran: a concentration index decomposition approach

OBJECTIVE

The present inquiry set to determine the economic inequality in history of stillbirth and understanding determinants of unequal distribution of stillbirth in Tehran, Iran.

METHODS

A population-based cross-sectional study was conducted on 5170 pregnancies in Tehran, Iran, since 2015. Principal component analysis (PCA) was applied to measure the asset-based economic status. Concentration index was used to measure socioeconomic inequality in stillbirth and then decomposed into its determinants.

RESULTS

The concentration index and its 95% CI for stillbirth was -0.121 (-0.235 to -0.002). Decomposition of the concentration index showed that mother's education (50%), mother's occupation (30%), economic status (26%) and father's age (12%) had the highest positive contributions to measured inequality in stillbirth history in Tehran. Mother's age (17%) had the highest negative contribution to inequality.

CONCLUSIONS

Stillbirth is unequally distributed among Iranian women and is mostly concentrated among low economic status people. Mother-related factors had the highest positive and negative contributions to inequality, highlighting specific interventions for mothers to redress inequality.

City-Specific Spatiotemporal Infant and Neonatal Mortality Clusters: Links with Socioeconomic and Air Pollution Spatial Patterns in France

Infant and neonatal mortality indicators are known to vary geographically, possibly as a result of socioeconomic and environmental inequalities. To better understand how these factors contribute to spatial and temporal patterns, we conducted a French ecological study comparing two time periods between 2002 and 2009 for three (purposefully distinct) Metropolitan Areas (MAs) and the city of Paris, using the French census block of parental residence as the geographic unit of analysis. We identified areas of excess risk and assessed the role of neighborhood deprivation and average nitrogen dioxide concentrations using generalized additive models to generate maps smoothed on longitude and latitude. Comparison of the two time periods indicated that statistically significant areas of elevated infant and neonatal mortality shifted northwards for the city of Paris, are present only in the earlier time period for Lille MA, only in the later time period for Lyon MA, and decrease over time for Marseille MA. These city-specific geographic patterns in neonatal and infant mortality are largely explained by socioeconomic and environmental inequalities. Spatial analysis can be a useful tool for understanding how risk factors contribute to disparities in health outcomes ranging from infant mortality to infectious disease-a leading cause of infant mortality.

Socioeconomic inequalities in stillbirth rates in Europe: measuring the gap using routine data from the Euro-Peristat Project

BACKGROUND

Previous studies have shown that socioeconomic position is inversely associated with stillbirth risk, but the impact on national rates in Europe is not known. We aimed to assess the magnitude of social inequalities in stillbirth rates in European countries using indicators generated from routine monitoring systems.

METHODS

Aggregated data on the number of stillbirths and live births for the year 2010 were collected for three socioeconomic indicators (mothers' educational level, mothers' and fathers' occupational group) from 29 European countries participating in the Euro-Peristat project. Educational categories were coded using the International Standard Classification of Education (ISCED) and analysed as: primary/lower secondary, upper secondary and postsecondary. Parents' occupations were grouped using International Standard Classification of Occupations (ISCO-08) major groups and then coded into 4 categories: No occupation or student, Skilled/ unskilled workers, Technicians/clerical/service occupations and Managers/professionals. We calculated risk ratios (RR) for stillbirth by each occupational group as well as the percentage population attributable risks using the most advantaged category as the reference (post-secondary education and professional/managerial occupations).

RESULTS

Data on stillbirth rates by mothers' education were available in 19 countries and by mothers' and fathers' occupations in 13 countries. In countries with these data, the median RR of stillbirth for women with primary and lower secondary education compared to women with postsecondary education was 1.9 (interquartile range (IQR): 1.5 to 2.4) and 1.4 (IQR: 1.2 to 1.6), respectively. For mothers' occupations, the median RR comparing outcomes among manual workers with managers and professionals was 1.6 (IQR: 1.0-2.1) whereas for fathers' occupations, the median RR was 1.4 (IQR: 1.2-1.8). When applied to the entire set of countries with data about mothers' education, 1606 out of 6337 stillbirths (25 %) would not have occurred if stillbirth rates for all women were the same as for women with post-secondary education in their country.

CONCLUSIONS

Data on stillbirths and socioeconomic status from routine systems showed widespread and consistent socioeconomic inequalities in stillbirth rates in Europe. Further research is needed to better understand differences between countries in the magnitude of the socioeconomic gradient.

Differences in perinatal and infant mortality in high-income countries: artifacts of birth registration or evidence of true differences?

Background

Variation in birth registration criteria may compromise international comparisons of fetal and infant mortality. We examined the effect of birth registration practices on fetal and infant mortality rates to determine whether observed differences in perinatal and infant mortality rates were artifacts of birth registration or reflected true differences in health status.

Methods

A retrospective population-based cohort study was done using data from Canada, United States, Denmark, Finland, Iceland, Norway, and Sweden from 1995–2005. Main outcome measures included live births by gestational age and birth weight; gestational age—and birth weight-specific stillbirth rates; neonatal, post-neonatal, and cause-specific infant mortality.

Results

Proportion of live births <22 weeks varied substantially: Sweden (not reported), Iceland (0.00 %), Finland (0.001 %), Denmark (0.01 %), Norway (0.02 %), Canada (0.07 %) and United States (0.08 %). At 22–23 weeks, neonatal mortality rates were highest in Canada (892.2 per 1000 live births), Denmark (879.3) and Iceland (1000.0), moderately high in the United States (724.1), Finland (794.3) and Norway (739.0) and low in Sweden (561.2). Stillbirth:live birth ratios at 22–23 weeks were significantly lower in the United States (79.2 stillbirths per 100 live births) and Finland (90.8) than in Canada (112.1), Iceland (176.2) and Norway (173.9). Crude neonatal mortality rates were 83 % higher in Canada and 96 % higher in the United States than Finland. Neonatal mortality rates among live births ≥28 weeks were lower in Canada and United States compared with Finland. Post-neonatal mortality rates were higher in Canada and United States than in Nordic countries.

Conclusions

Live birth frequencies and stillbirth and neonatal mortality patterns at the borderline of viability are likely due to differences in birth registration practices, although true differences in maternal, fetal and infant health cannot be ruled out. This study emphasises the need for further standardisations, in order to enhance the relevance of international comparisons of infant mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-015-0430-8) contains supplementary material, which is available to authorized users.

Assumptions about culture in discourse on ethnic minority health

This paper is interested in the way the concept of culture is deployed in documents aimed at investigating, informing on and promoting aspects of ethnic minority health. Within a health-political discourse focusing increasingly on individual lifestyles, ethnic minority health became subject to increased political and professional interest in the last decades of the twentieth and the first decade of the twenty-first century. Analysis of the discourse on ethnic minority health emerging in five texts addressing health professionals shows that the culture of ethnic minority citizens is primarily seen as contributing to low levels of knowledge about health and to adverse health behavior. Thus, the texts present cultural beliefs and practices as contributing to the high prevalence of lifestyle diseases among ethnic minority population groups. The analysis, however, demonstrates that a more nuanced discourse is evolving, taking the complexity of the culture concept into account. In accordance with Danish health-political priorities, the most recent text analyzed in this study promotes an individualistic approach to both ethnic minority and Danish ethnic majority citizens.

An exploratory spatial analysis to assess the relationship between deprivation, noise and infant mortality: an ecological study

BACKGROUND

Few studies have explored how noise might contribute to social health inequalities, and even fewer have considered infant mortality or its risk factors as the health event of interest.In this paper, we investigate the impact of neighbourhood characteristics - both socio-economic status and ambient noise levels - on the spatial distribution of infant mortality in the Lyon metropolitan area, in France.

METHODS

All infant deaths (n = 715) occurring between 2000 and 2009 were geocoded at census block level. Each census block was assigned multi-component socio-economic characteristics and Lden levels, which measure exposure to noise. Using a spatial-scan statistic, we examined whether there were significant clusters of high risk of infant mortality according to neighbourhood characteristics.

RESULTS

Our results highlight the fact that infant mortality is non-randomly distributed spatially, with clusters of high risk in the south-east of the Lyon metropolitan area (RR = 1.44; p = 0.09). After adjustments for socio-economic characteristics and noise levels, this cluster disappears or shifts according to in line with different scenarios, suggesting that noise and socio-economic characteristics can partially explain the spatial distribution of infant mortality.

CONCLUSION

Our findings show that noise does have an impact on the spatial distribution of mortality after adjustments for socio-economic characteristics. A link between noise and infant mortality seems plausible in view of the three hypothetical, non-exclusive, pathways we propose in our conceptual framework: (i) a psychological pathway, (ii) a physiological disruption process and (iii) an unhealthy behaviours pathway. The lack of studies makes it is difficult to compare our findings with others. They require further research for confirmation and interpretation.

The social determinants of infant mortality and birth outcomes in Western developed nations: a cross-country systematic review

Infant mortality (IM) and birth outcomes, key population health indicators, have lifelong implications for individuals, and are unequally distributed globally. Even among western industrialized nations, striking cross-country and within-country patterns are evident. We sought to better understand these variations across and within the United States of America (USA) and Western Europe (WE), by conceptualizing a social determinants of IM/birth outcomes framework, and systematically reviewing the empirical literature on hypothesized social determinants (e.g., social policies, neighbourhood deprivation, individual socioeconomic status (SES)) and intermediary determinants (e.g., health behaviours). To date, the evidence suggests that income inequality and social policies (e.g., maternal leave policies) may help to explain cross-country variations in IM/birth outcomes. Within countries, the evidence also supports neighbourhood SES (USA, WE) and income inequality (USA) as social determinants. By contrast, within-country social cohesion/social capital has been underexplored. At the individual level, mixed associations have been found between individual SES, race/ethnicity, and selected intermediary factors (e.g., psychosocial factors) with IM/birth outcomes. Meanwhile, this review identifies several methodological gaps, including the underuse of prospective designs and the presence of residual confounding in a number of studies. Ultimately, addressing such gaps including through novel approaches to strengthen causal inference and implementing both health and non-health policies may reduce inequities in IM/birth outcomes across the western developed world.

Freestanding midwifery units versus obstetric units: does the effect of place of birth differ with level of social disadvantage?

Background

Social inequity in perinatal and maternal health is a well-documented health problem even in countries with a high level of social equality. We aimed to study whether the effect of birthplace on perinatal and maternal morbidity, birth interventions and use of pain relief among low risk women intending to give birth in two freestanding midwifery units (FMU) versus two obstetric units in Denmark differed by level of social disadvantage.

Methods

The study was designed as a cohort study with a matched control group. It included 839 low-risk women intending to give birth in an FMU, who were prospectively and individually matched on nine selected obstetric/socio-economic factors to 839 low-risk women intending OU birth. Educational level was chosen as a proxy for social position. Analysis was by intention-to-treat.

Results

Women intending to give birth in an FMU had a significantly higher likelihood of uncomplicated, spontaneous birth with good outcomes for mother and infant compared to women intending to give birth in an OU. The likelihood of intact perineum, use of upright position for birth and water birth was also higher. No difference was found in perinatal morbidity or third/fourth degree tears, while birth interventions including caesarean section and epidural analgesia were significantly less frequent among women intending to give birth in an FMU. In our sample of healthy low-risk women with spontaneous onset of labour at term after an uncomplicated pregnancy, the positive results of intending to give birth in an FMU as compared to an OU were found to hold for both women with post-secondary education and the potentially vulnerable group of FMU women without post-secondary education. In all cases, women without post-secondary education intending to give birth in an FMU had comparable and, in some respects, more favourable outcomes when compared to women with the same level of education intending to give birth in an OU. In this sample of low-risk women, we found that the effect of intended place on birth outcomes did not differ with women’s level of education.

Conclusion

FMU care appears to offer important benefits for birthing women with no additional risk to the infant. Both for women with and without post-secondary education, intending to give birth in an FMU significantly increased the likelihood of a spontaneous, uncomplicated birth with good outcomes for mother and infant compared to women intending to give birth in an OU. All women should be provided with adequate information about different care models and supported in making an informed decision about the place of birth.

Socioeconomic differences in perinatal health and disease

INTRODUCTION

The Danish Medical Birth Register has been used extensively in conjunction with other national registers to examine different aspects of socioeconomic differences in perinatal health outcomes. Here, we review some recent findings.

RESEARCH TOPICS

Socioeconomic differences were observed in stillbirth, preterm birth, birthweight, congenital anomalies, and infant death. The patterns varied according to the health outcome and measure of socioeconomic position, but also according to the time period and the country under study. Our review also shows how many different strategies have been used to examine the influence of socioeconomic factors on perinatal health.

CONCLUSION

Danish register data is an invaluable source of information on socioeconomic differences in perinatal health. Danish registers continue to provide excellent opportunities for research and surveillance in this area.

Stillbirths: the way forward in high-income countries

Stillbirth rates in high-income countries declined dramatically from about 1940, but this decline has slowed or stalled over recent times. The present variation in stillbirth rates across and within high-income countries indicates that further reduction in stillbirth is possible. Large disparities (linked to disadvantage such as poverty) in stillbirth rates need to be addressed by providing more educational opportunities and improving living conditions for women. Placental pathologies and infection associated with preterm birth are linked to a substantial proportion of stillbirths. The proportion of unexplained stillbirths associated with under investigation continues to impede efforts in stillbirth prevention. Overweight, obesity, and smoking are important modifiable risk factors for stillbirth, and advanced maternal age is also an increasingly prevalent risk factor. Intensified efforts are needed to ameliorate the effects of these factors on stillbirth rates. Culturally appropriate preconception care and quality antenatal care that is accessible to all women has the potential to reduce stillbirth rates in high-income countries. Implementation of national perinatal mortality audit programmes aimed at improving the quality of care could substantially reduce stillbirths. Better data on numbers and causes of stillbirth are needed, and international consensus on definition and classification related to stillbirth is a priority. All parents should be offered a thorough investigation including a high-quality autopsy and placental histopathology. Parent organisations are powerful change agents and could have an important role in raising awareness to prevent stillbirth. Future research must focus on screening and interventions to reduce antepartum stillbirth as a result of placental dysfunction. Identification of ways to reduce maternal overweight and obesity is a high priority for high-income countries.

Health inequality: what does it mean and how can we measure it?

Reducing socioeconomic inequalities in health has become an important government objective. International organizations, such as the WHO, have played an important role providing the principles to encourage action in many countries. Evidence of socioeconomic inequalities in health is widespread. National and cross-national research has led to the development of a new set of methodological tools to address the challenges that the available data present. Several methods have been used in the literature to measure inequalities in health; the concentration index approach is becoming widely used. In the future, the research agenda will continue to shift away from documenting health inequalities toward efforts to support the development of policies to improve the health of the most deprived populations and to reduce inequalities in health.

Women want proactive psychosocial support from midwives during transition to motherhood: a qualitative study

OBJECTIVE

to explore low-risk pregnant women's views on their preferences for psychosocial support from midwives during their transition to motherhood.

DESIGN

a qualitative design with focus-group interviews and thematic analysis of the discussions. SETTINGS AND RESPONDENTS: 21 Dutch participants were included in three focus groups. Groups 1 (n=7) and 3 (n=8) consisted of pregnant women from four semi-urban midwifery practices, and group 2 (n=6) included participants from three urban midwifery practices.

FINDINGS

the women wanted to take responsibility for their own well-being during pregnancy. In addition to informal support, they explicitly expressed a need for professional support from their midwives when undergoing the transition to motherhood. They wanted informational and emotional support from their midwives that addressed psychological and physical changes during pregnancy. They expressed a strong desire to be informed during pregnancy of how to prepare physically and psychologically for birth, recovery and motherhood. They also wanted help with sifting and interpreting information and, ultimately, wanted to make their own choices.

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

during their transition to motherhood, healthy low-risk pregnant women want attentive, proactive, professional psychosocial support from midwives. They expect their midwives to oversee the transition period and to be capable of supporting them in dealing with changes in pregnancy and in preparing for birth and motherhood.

Contribution of smoking during pregnancy to inequalities in stillbirth and infant death in Scotland 1994-2003: retrospective population based study using hospital maternity records

OBJECTIVE

To quantify the contribution of smoking during pregnancy to social inequalities in stillbirth and infant death.

DESIGN

Population based retrospective cohort study.

SETTING

Scottish hospitals between 1994 and 2003.

PARTICIPANTS

Records of 529 317 singleton live births and 2699 stillbirths delivered at 24-44 weeks' gestation in Scotland from 1994 to 2003.

MAIN OUTCOME MEASURES

Rates of stillbirth and infant, neonatal, and post-neonatal death for each deprivation category (fifths of postcode sector Carstairs-Morris scores); contribution of smoking during pregnancy ("no," "yes," or "not known") in explaining social inequalities in these outcomes.

RESULTS

The stillbirth rate increased from 3.8 per 1000 in the least deprived group to 5.9 per 1000 in the most deprived group. For infant deaths, the rate increased from 3.2 per 1000 in the least deprived group to 5.4 per 1000 in the most deprived group. Stillbirths were 56% more likely (odds ratio 1.56, 95% confidence interval 1.38 to 1.77) and infant deaths were 72% more likely (1.72, 1.50 to 1.97) in the most deprived compared with the least deprived category. Smoking during pregnancy accounted for 38% of the inequality in stillbirths and 31% of the inequality in infant deaths.

CONCLUSIONS

Both tackling smoking during pregnancy and reducing infants' exposure to tobacco smoke in the postnatal environment may help to reduce stillbirths and infant deaths overall and to reduce the socioeconomic inequalities in stillbirths and infant deaths perhaps by as much as 30-40%. However, action on smoking on its own is unlikely to be sufficient and other measures to improve the social circumstances, social support, and health of mothers and infants are needed.