Immigrants and Preterm Births: A Nationwide Epidemiological Study in Sweden

Exploring Predictors of Preterm Birth: A Comparative Study of Turkish and Syrian Refugee Women

OBJECTIVE

This study is designed to explore associated sociodemographic, birth-related and household characteristics with preterm birth (< 37 weeks) among Turkish and Syrian refugee women.

METHODS

The data utilized in this study were obtained from the Turkey Demographic and Health Survey (TDHS) conducted in 2018. Various statistical analyses, including descriptive statistics, independent sample t-tests, and Chi-square tests, were employed to examine the differences in study variables between Turkish and Syrian refugee women. Furthermore, logistic regression analysis was conducted to identify the associated factors with preterm birth among Turkish and Syrian refugee women, allowing for comparative analysis.

RESULTS

The key findings of this study revealed significant differences in sociodemographic (p < 0.05), birth-related (p < 0.05), and household characteristics (p < 0.05) that are associated with preterm birth among Turkish and Syrian refugee women. Also, nationality (OR: 3.427; 95% CI 2.770-4.241), delivery by c-section (OR: 1.630; 95% CI 1.370-1.939), educational status (OR: 0.674; 95% CI 0.547-0.832), place of delivery (OR: 0.806; 95% CI 0.666-0.975), and number of household members (OR: 1.206; 95% CI 1.013-1.437) were found to be important factors associated with preterm birth risk.

CONCLUSIONS

The key findings of this study contribute to the identification of women's factors in preterm birth. By understanding the factors that contribute to preterm birth among both Syrian refugee and Turkish women, appropriate interventions can be developed to improve maternal and child health outcomes.

Prevalence of preterm birth in Scandinavian countries: a systematic review and meta-analysis

OBJECTIVES

As welfare societies, Scandinavian countries share characteristics of equality related to healthcare access, gender, and social services. However, cultural and lifestyle variations create country-specific health differences. This meta-analysis assessed the prevalence of preterm birth (PTB) and its categories in Scandinavian countries.

METHODS

A systematic search in key databases of literature published between 1990 and 2021 identified studies of the prevalence of PTB and its categories. Following the use of the Freeman-Tukey double arcsine transformation, a meta-analysis of weighted data was performed using the random-effects model and meta-prop method.

RESULTS

We identified 109 observational studies that involved 86,420,188 live births. The overall pooled prevalence (PP) of PTB was 5.3% (PP = 5.3%, 95% confidence interval [CI] 5.1%, 5.5%). The highest prevalence was in Norway (PP = 6.2%, 95% CI 5.3%, 7.0%), followed by Sweden (PP = 5.3%, 95% CI 5.1%, 5.4%), Denmark (PP = 5.2%, 95% CI 4.9%, 5.3%), and Iceland (PP = 5.0%, 95% CI 4.4%, 5.7%). Finland had the lowest PTB rate (PP = 4.9%, 95% CI 4.7%, 5.1%).

CONCLUSIONS

The overall PP of PTB was 5.3%, with small variations among countries (4.9%-6.2%). The highest and lowest PPs of PTB were in Norway and Finland, respectively.

Adverse Pregnancy Outcomes and International Immigration Status: A Systematic Review and Meta-analysis

Background:

Disparities in health outcomes between immigrant and native-origin populations, particularly pregnant women, pose significant challenges to healthcare systems. The aim of this systematic-review and meta-analysis was to investigate the risk of adverse pregnancy outcomes among immigrant-women compared to native-origin women in the host country.

Methods:

PubMed (including MEDLINE), Scopus, and Web of Science were searched to retrieve studies published in English language up to September 2020. All observational studies examining the prevalence of at least one of the short-term single pregnancy outcomes for immigrants who crossed international borders compared to native-origin pregnant population were included. The meta-prop method was used for the pooled-estimation of adverse pregnancy-outcomes’ prevalence. For pool-effect estimates, the association between the immigration-status and outcomes of interest, the random-effects model was applied using the model described by DerSimonian and Laird. I² statistic was used to assess heterogeneity. The publication bias was assessed using the Harbord-test. Meta-regression was performed to explore the effect of geographical region as the heterogeneity source.

Findings:

This review involved 11 320 674 pregnant women with an immigration-background and 56 102 698 pregnant women as the native-origin population. The risk of emergency cesarean section (Pooled-OR = 1.1, 95%CI = 1.0–1.2), shoulder dystocia (Pooled-OR = 1.1, 95%CI = 1.0–1.3), gestational diabetes mellites (Pooled-OR = 1.4, 95%CI = 1.2–1.6), small for gestational age (Pooled-OR=1.3, 95%CI = 1.1–0.4), 5-min Apgar less than 7 (Pooled-OR = 1.2, 95%CI = 1.0–1.3) and oligohydramnios (Pooled-OR = 1.8, 95%CI = 1.0–3.3) in the immigrant women were significantly higher than those with the native origin background. The immigrant women had a lower risk of labor induction (Pooled-OR = 0.8, 95%CI = 0.7–0.8), pregnancy induced hypertension (Pooled-OR = 0.6, 95%CI = 0.5–0.7) preeclampsia (Pooled-OR = 0.7, 95%CI = 0.6–0.8), macrosomia (Pooled-OR = 0.8, 95%CI = 0.7–0.9) and large for gestational age (Pooled-OR = 0.8, 95%CI = 0.7–0.8). Also, the risk of total and primary cesarean section, instrumental-delivery, preterm-birth, and birth-trauma were similar in both groups. According to meta-regression analyses, the reported ORs were not influenced by the country of origin.

Conclusion:

The relationship between the immigration status and adverse perinatal outcomes indicated a heterogenous pattern, but the immigrant women were at an increased risk of some important adverse pregnancy outcomes. Population-based studies with a focus on the various aspects of this phenomena are required to explain the source of these heterogenicities.

A Systematic Review and Meta-Analysis of the Risk of Stillbirth, Perinatal and Neonatal Mortality in Immigrant Women

Objectives: This study aimed to investigate the risk of stillbirth, perinatal and neonatal mortality in immigrant women compared to native-origin women in host countries.

Methods: A systematic literature review and meta-analysis was conducted. Relevant studies were identified using a thorough literature search and their quality was appraised. The analysis of heterogeneous data was carried out using the random effects model and publication bias was assessed using the Harbord-test. Also, the pooled odds ratio of events was calculated through the DerSimonian and Laird, and inverse variance methods.

Results: In the search process 45 studies were retrieved consisting of 8,419,435 immigrant women and 40,113,869 native-origin women. The risk of stillbirth (Pooled OR = 1.35, 95% CI = 1.22–1.50), perinatal mortality (Pooled OR = 1.50, 95% CI = 1.35–1.68), and neonatal mortality (Pooled OR = 1.09, 95% CI = 1.00–1.19) in the immigrant women were significantly higher than the native-origin women in host countries. According to the sensitivity analyses, all results were highly consistent with the main data analysis results.

Conclusion: The immigrant women compared to the native-origin women had the higher risks of stillbirth, perinatal and neonatal mortality. Healthcare providers and policy makers should improve the provision of maternal and neonatal healthcare for the immigrant population.

Association between maternal country of birth and preterm birth: A population-based register study of 910,752 deliveries

Aims: The aim of this study was to analyse associations between maternal country of birth and preterm birth among women giving birth in Norway. Methods: A population-based register study was conducted employing official national databases in Norway. All singleton births, with neonates without major anomalies, between 1999 and 2014 were included (N=910,752). We estimated odds ratios (ORs) for extremely preterm birth (<28 weeks gestation), very preterm birth (28–33 weeks gestation) and late preterm birth (34–36 weeks gestation) by maternal country of birth. We conducted multivariable regression analyses, adjusting for maternal, obstetric and socio-economic confounders. Results: For extremely preterm births (0.4% of the study population), women with an unknown country of birth (adjusted OR (aOR)=3.09; 95% confidence interval (CI) 2.26–4.22) and women born in sub-Saharan Africa (aOR=1.66; CI 1.40–1.96) had the highest ORs compared to Norwegian-born women. For very preterm births (1.2% of the study population), women with an unknown country of birth (aOR=1.72; CI 1.36–2.18) and women born in South Asia (aOR=1.48; CI 1.31–1.66) had the highest ORs. For late preterm births (3.8% of the study population), women born in East Asia Pacific/Oceania (aOR=1.33; CI 1.25–1.41) and South Asia (aOR=1.30; CI 1.21–1.39) had the highest ORs. Conclusions: After adjusting for maternal, obstetric and socio-economic risk factors, maternal country of birth remained significantly associated with preterm birth. Women with an unknown country of birth and women born in sub-Saharan Africa were found to be at increased risk of extremely preterm birth.

[How to measure the migration status of the child and young population? Studies on health and inequalities in health in Europe]

OBJECTIVE

To analyse how the migration status of the child and young population is measured in the scientific literature on health and social inequalities in health in Europe.

METHOD

A systematic search of the literature published in Spanish, English and French between 2007 and 2017 in PubMed and Social Sciences Citation Index was carried out. The included studies analysed health and social inequalities in health of a population under 18 years old according to its migration origin in Europe. The variables used to measure the migration status were described.

RESULTS

50 articles were included. Twenty studies analysed perinatal health, eleven mental health, nine dental health, and ten studies other variables. The main variables to define migration status were the country of birth (32 studies), either of the child, the mother, or one of the parents, and sometimes in a complementary way. Less frequent was the use of nationality (15 studies), of the child, or of the parents, especially the mother. Migration status is referred to in very different ways, not always comparable and sometimes the variable used is not clearly explained.

CONCLUSIONS

There is a great diversity of ways to measure migration status in the child and young population. A better definition and consensus is needed to improve the temporal and geographical comparability of knowledge in this area, which will help to design public policies aimed at reducing social inequalities in health from childhood.

Epilepsy in second-generation immigrants: a cohort study of all children up to 18 years of age in Sweden

BACKGROUND AND PURPOSE

Our purpose was to study the association between country of birth and incident epilepsy in second-generation immigrants in Sweden.

METHODS

The study population included all children (n = 4 023 149) aged up to 18 years in Sweden. Epilepsy was defined as at least one registered diagnosis of epilepsy in the National Patient Register. The incidence of epilepsy, using individuals with Swedish-born parents as referents, was assessed by Cox regression, expressed in hazard ratios (HRs) and 95% confidence interval (95% CI). All models were stratified by sex and adjusted for age, geographical residence in Sweden, educational level, marital status, neighbourhood socioeconomic status and comorbid conditions, also using data from the Total Population Register.

RESULTS

A total of 26 310 individuals had a registered epilepsy event, i.e. 6.5/1000 (6.6/1000 amongst boys and 6.3/1000 amongst girls). After adjustment, the risk of epilepsy was lower than in children of Swedish-born parents. Amongst girls the significant HR was 0.85 (95% CI 0.81-0.88), but in boys only when adjusting also for comorbidity (HR 0.96, 95% CI 0.92-0.99). Amongst specific immigrant groups, a higher incidence of epilepsy was observed amongst boys with parents from Turkey and Africa, but not when adjusting for comorbidity, and a lower risk was observed in many other groups (boys with parents from Latvia, girls with parents from Finland, Iceland, Southern Europe, countries from the former Yugoslavia, and Asia).

CONCLUSION

The risk of epilepsy was lower in second-generation immigrant children compared to children with Swedish-born parents, but with substantial differences between different immigrant groups.

Gestational age at birth and risk of intellectual disability without a common genetic cause

Preterm birth is linked to intellectual disability and there is evidence to suggest post-term birth may also incur risk. However, these associations have not yet been investigated in the absence of common genetic causes of intellectual disability, where risk associated with late delivery may be preventable. We therefore aimed to examine risk of intellectual disability without a common genetic cause across the entire range of gestation, using a matched-sibling design to account for unmeasured confounding by shared familial factors. We conducted a population-based retrospective study using data from the Stockholm Youth Cohort (n = 499,621) and examined associations in a nested cohort of matched outcome-discordant siblings (n = 8034). Risk of intellectual disability was greatest among those born extremely early (adjusted OR_{24 weeks} = 14.54 [95% CI 11.46-18.44]), lessening with advancing gestational age toward term (aOR_{32 weeks} = 3.59 [3.22-4.01]; aOR_37weeks = 1.50 [1.38-1.63]); aOR_{38 weeks} = 1.26 [1.16-1.37]; aOR₃₉ weeks = 1.10 [1.04-1.17]) and increasing with advancing gestational age post-term (aOR_{42 weeks} = 1.16 [1.08-1.25]; aOR_{43 weeks} = 1.41 [1.21-1.64]; aOR_{44 weeks} = 1.71 [1.34-2.18]; aOR_{45 weeks} = 2.07 [1.47-2.92]). Associations persisted in a cohort of matched siblings suggesting they were robust against confounding by shared familial traits. Risk of intellectual disability was greatest among children showing evidence of fetal growth restriction, especially when birth occurred before or after term. Birth at non-optimal gestational duration may be linked causally with greater risk of intellectual disability. The mechanisms underlying these associations need to be elucidated as they are relevant to clinical practice concerning elective delivery around term and mitigation of risk in post-term children.

What contributes to disparities in the preterm birth rate in European countries?

PURPOSE OF REVIEW

In countries with comparable levels of development and healthcare systems, preterm birth rates vary markedly--a range from 5 to 10% among live births in Europe. This review seeks to identify the most likely sources of heterogeneity in preterm birth rates, which could explain differences between European countries.

RECENT FINDINGS

Multiple risk factors impact on preterm birth. Recent studies reported on measurement issues, population characteristics, reproductive health policies as well as medical practices, including those related to subfertility treatments and indicated deliveries, which affect preterm birth rates and trends in high-income countries. We showed wide variation in population characteristics, including multiple pregnancies, maternal age, BMI, smoking, and percentage of migrants in European countries.

SUMMARY

Many potentially modifiable population factors (BMI, smoking, and environmental exposures) as well as health system factors (practices related to indicated preterm deliveries) play a role in determining preterm birth risk. More knowledge about how these factors contribute to low and stable preterm birth rates in some countries is needed for shaping future policy. It is also important to clarify the potential contribution of artifactual differences owing to measurement.

Health, growth and psychosocial adaptation of immigrant children

The increasing population diversity in Europe demands clarification of possible ethnic influences on the growth and health of immigrant children and their psychosocial adaptation to the host countries. This article assesses recent data on immigrant children in Europe in comparison to European natives by means of a systematic review of the literature on growth patterns and data on children's health and adaptation. There were wide variations across countries in growth patterns and development of immigrant children and natives, with different trends in Central and Northern Europe with respect to Southern Europe. In general, age at menarche was lower in immigrant girls, while male pubertal progression seemed faster in immigrants than in European natives, even when puberty began after. Owing to the significant differences in anthropometric traits (mainly stature and weight), new reference growth curves for immigrant children were constructed for the largest minority groups in Central Europe. Possible negative effects on growth, health and psychosocial adaptation were pointed out for immigrant children living in low income, disadvantaged communities with a high prevalence of poor lifestyle habits. In conclusion, this review provides a framework for the health and growth of immigrant children in Europe in comparison to native-born children: the differences among European countries in growth and development of migrants and non-migrants are closely related to the clear anthropological differences among the ethnic groups due to genetic influences. Higher morbidity and mortality was frequently associated with the minority status of these children and their low socio-economic status. The observed ethnic differences in health reveal the need for adequate health care in all groups. Therefore, we provide suggestions for the development of health care strategies in Europe.