Preterm and postterm birth in immigrant- and Swedish-born parents: a population register-based study

Effect of access to antenatal care on risk of preterm birth among migrant women in Italy: A population-based cohort study

Objective

To evaluate the association between maternal migration status and preterm birth, and whether a better adherence to antenatal care during pregnancy mitigates the risk of preterm birth.

Design

Population-based cohort.

Setting

Administrative databases of the Lombardy region, Italy.

Population

First singleton births of women aged 15-55 years at 22-42 gestational weeks, between 2016 and 2021.

Methods

Assessed the risk of preterm birth (<37 weeks).

Main outcome measures

A multivariable logistic regression mediation model calculated the mediation effect of adherence to antenatal care in the association between maternal migrant status and preterm birth and the residual effect not mediated by it. Analyses were adjusted for the socio-demographic and pregnant characteristics of the women.

Results

Of 349,753 births in the cohort, Italian nationality accounted for 71 %; 28.4 % were documented migrants and 0.4 % undocumented migrants. Among them, 5.3 %, 6.4 %, and 9.3 % had a preterm birth, respectively. Using deliveries of Italian citizens as referent, migrants had a significantly increased risk of preterm birth (adjusted relative risk: 1.22, 95 % confidence interval: 1.18-1.27). Adherence to antenatal care mediated the 62 % of such risk. We have calculated that adherence to antenatal pathways set to the highest level for the whole population could lead to a 37 % reduction in preterm birth risk.

Conclusion

Part of the excess of preterm birth among documented and undocumented migrants in Italy can be explained by a lack of adherence to the antenatal care path despite equal access to National Health care. The adherence of all pregnant women to antenatal care would reduce the risk of preterm birth by about one-third.

The prevalence of preterm and low birth weight infants among migrant women in the Pearl River Delta region, China: a population-based birth cohort study

BACKGROUND

The existing literature evaluating the association between neonatal morbidity and migrant status presents contradictory results. The purpose of this study was to compare the risk of preterm birth (PTB) and low birth weight (LBW) among newborns from local and migrant women in China's Pearl River Delta (PRD) region.

METHODS

In this observational population-based study, we included all live singleton deliveries from PRD region local women and migrant women. Data were sourced from the Guangdong Medical Birth Registry Information System between Jan 1, 2014, and Dec 31, 2020. Women were categorized into three groups by maternal migrant status: local women from PRD region, migrant women from Guangdong province or from other provinces. The outcome variables that were examined included two adverse birth outcomes: PTB and LBW. The association between the risk of PTB and LBW and maternal migrant status was assessed using logistic regression.

RESULTS

During 2014-2020, 5,219,133 single live deliveries were recorded, corresponding 13.22% to local women and the rest to migrant women coming from Guangdong (53.51%) and other provinces (33.26%). PTB prevalence was highest among local women (5.79%), followed by migrant women from Guangdong (5.29%), and the lowest among migrants from other provinces (4.95%). This association did not change after including maternal age, infant sex, delivery mode, and birth season in the models. Compared to local women, migrant women from other provinces had a lower risk of LBW (4.00% vs. 4.98%, P < 0.001). The prevalence of PTB and LBW was higher among local women than migrants. The odds of delivery PTB and LBW were higher for women who were age ≥ 35. Among the three maternal migration groups, the age-LBW association displayed a typical U-shaped pattern, with those in the youngest (16-24 years) and oldest (≥ 35) age categories exhibiting the higher odds of delivering a LBW neonate. With respect to infant sex, the prevalence of PTB was significantly higher in males than females among the three maternal migration groups. An opposite trend was found for LBW, and the prevalence of LBW was higher in females among the three maternal migration groups.

CONCLUSION

The findings of this study contribute to the understanding of the epidemiology of PTB and LBW among migrant women. Our study suggests that it is the health and robust nature of migrant mothers that predisposes them to better birth outcomes. It is important to recognize that the results of this study, while supportive of the healthy migrant effect, cannot be considered definitive without some exploration of motivation for moving and changes in lifestyle postmigration.

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.

Group antenatal care compared with standard antenatal care for Somali-Swedish women: a historically controlled evaluation of the Hooyo Project

OBJECTIVES

Comparing language-supported group antenatal care (gANC) and standard antenatal care (sANC) for Somali-born women in Sweden, measuring overall ratings of care and emotional well-being, and testing the feasibility of the outcome measures.

DESIGN

A quasi-experimental trial with one intervention and one historical control group, nested in an intervention development and feasibility study.

SETTING

Midwifery-led antenatal care clinic in a mid-sized Swedish town.

PARTICIPANTS

Pregnant Somali-born women (<25 gestational weeks); 64 women in gANC and 81 in sANC.

INTERVENTION

Language-supported gANC (2017-2019). Participants were offered seven 60-minute group sessions with other Somali-born women led by one to two midwives, in addition to 15-30 min individual appointments with their designated midwife.

OUTCOMES

Primary outcomes were women's overall ratings of antenatal care and emotional well-being (Edinburgh Postnatal Depression Scale (EPDS)) in gestational week ≥35 and 2 months post partum. Secondary outcomes were specific care experiences, information received, social support, knowledge of pregnancy danger signs and obstetric outcomes.

RESULTS

Recruitment and retention of participants were challenging. Of eligible women, 39.3% (n=106) declined to participate. No relevant differences regarding overall ratings of antenatal care between the groups were detected (late pregnancy OR 1.42, 95% CI 0.50 to 4.16 and 6-8 weeks post partum OR 2.71, 95% CI 0.88 to 9.41). The reduction in mean EPDS score was greater in the intervention group when adjusting for differences at baseline (mean difference -1.89; 95% CI -3.73 to -0.07). Women in gANC were happier with received pregnancy and birth information, for example, caesarean section where 94.9% (n=37) believed the information was sufficient compared with 17.5% (n=7) in standard care (p<0.001) in late pregnancy.

CONCLUSIONS

This evaluation suggests potential for language-supported gANC to improve knowledge acquisition among pregnant Somali-born women with residence in Sweden ˂10 years. An adequately powered randomised trial is needed to evaluate the effectiveness of the intervention.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT03879200).

Health-related quality of life of children born very preterm: a multinational European cohort study

PURPOSE

This study aims to (1) describe the health-related quality of life (HRQoL) outcomes experienced by children born very preterm (28-31 weeks' gestation) and extremely preterm (< 28 weeks' gestation) at five years of age and (2) explore the mediation effects of bronchopulmonary dysplasia (BPD) and severe non-respiratory neonatal morbidity on those outcomes.

METHODS

This investigation was based on data for 3687 children born at < 32 weeks' gestation that contributed to the EPICE and SHIPS studies conducted in 19 regions across 11 European countries. Descriptive statistics and multi-level ordinary linear squares (OLS) regression were used to explore the association between perinatal and sociodemographic characteristics and PedsQL^™ GCS scores. A mediation analysis that applied generalised structural equation modelling explored the association between potential mediators and PedsQL^™ GCS scores.

RESULTS

The multi-level OLS regression (fully adjusted model) revealed that birth at < 26 weeks' gestation, BPD status and experience of severe non-respiratory morbidity were associated with mean decrements in the total PedsQL^™ GCS score of 0.35, 3.71 and 5.87, respectively. The mediation analysis revealed that the indirect effects of BPD and severe non-respiratory morbidity on the total PedsQL^™ GCS score translated into decrements of 1.73 and 17.56, respectively, at < 26 weeks' gestation; 0.99 and 10.95, respectively, at 26-27 weeks' gestation; and 0.34 and 4.80, respectively, at 28-29 weeks' gestation (referent: birth at 30-31 weeks' gestation).

CONCLUSION

The findings suggest that HRQoL is particularly impaired by extremely preterm birth and the concomitant complications of preterm birth such as BPD and severe non-respiratory morbidity.

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.

Perinatal risk factors for mortality in very preterm infants-A nationwide, population-based discriminant analysis

Aim

To assess the strength of associations between interrelated perinatal risk factors and mortality in very preterm infants.

Methods

Information on all live‐born infants delivered in Sweden at 22–31 weeks of gestational age (GA) from 2011 to 2019 was gathered from the Swedish Neonatal Quality Register, excluding infants with major malformations or not resuscitated because of anticipated poor prognosis. Twenty‐seven perinatal risk factors available at birth were exposures and in‐hospital mortality outcome. Orthogonal partial least squares discriminant analysis was applied to assess proximity between individual risk factors and mortality, and receiver operating characteristic (ROC) curves were used to estimate discriminant ability.

Results

In total, 638 of 8,396 (7.6%) infants died. Thirteen risk factors discriminated reduced mortality; the most important were higher Apgar scores at 5 and 10 min, GA and birthweight. Restricting the analysis to preterm infants <28 weeks’ GA (n = 2939, 16.9% mortality) added antenatal corticosteroid therapy as significantly associated with lower mortality. The area under the ROC curve (the C‐statistic) using all risk factors was 0.86, as determined after both internal and external validation.

Conclusion

Apgar scores, gestational age and birthweight show stronger associations with mortality in very preterm infants than several other perinatal risk factors available at birth.

Perinatal and Neonatal Outcomes in Immigrants From Conflict-Zone Countries: A Systematic Review and Meta-Analysis of Observational Studies

Objectives

There are controversies regarding the risk of adverse pregnancy outcomes among immigrants from conflict-zone countries. This systematic review and meta-analysis aimed to investigate the risk of perinatal and neonatal outcomes among immigrants from conflict-zone countries compared to native-origin women in host countries.

Methods

A systematic search on the databases of PubMed/MEDLINE, Scopus, and Web of Science was carried out to retrieve studies on perinatal and neonatal outcomes among immigrants from Somalia, Iraq, Afghanistan, Yemen, Syria, Nigeria, Sudan, Ethiopia, Eritrea, Kosovo, Ukraine, and Pakistan. Only peer-reviewed articles published in the English language were included in the data analysis and research synthesis. The odds ratio and forest plots were constructed for assessing the outcomes of interests using the DerSimonian and Laird, and the inverse variance methods. The random-effects model and the Harbord test were used to account for heterogeneity between studies and assess publication bias, respectively. Further sensitivity analysis helped with the verification of the reliability and stability of our review results.

Results

The search process led to the identification of 40 eligible studies involving 215,718 pregnant women, with an immigration background from the conflict zone, and 12,806,469 women of native origin. The adverse neonatal outcomes of the risk of small for gestational age (Pooled OR = 1.8, 95% CI = 1.6, 2.1), a 5-min Apgar score <7 (Pooled OR = 1.4, 95% CI = 1.0, 2.1), stillbirth (Pooled OR = 1.9, 95% CI = 1.2, 3.0), and perinatal mortality (Pooled OR = 2, 95% CI = 1.6, 2.5) were significantly higher in the immigrant women compared to the women of native-origin. The risk of maternal outcomes, including the cesarean section (C-S) and emergency C-S, instrumental delivery, preeclampsia, and gestational diabetes was similar in both groups.

Conclusion

Although the risk of some adverse maternal outcomes was comparable in the groups, the immigrant women from conflict-zone countries had a higher risk of neonatal mortality and morbidity, including SGA, a 5-min Apgar score <7, stillbirth, and perinatal mortality compared to the native-origin population. Our review results show the need for the optimization of health care and further investigation of long-term adverse pregnancy outcomes among immigrant women.

Extremely and Very Preterm Deliveries in a Maternity Unit of Inappropriate Level: Analysis of Socio-Residential Factors

PURPOSE

To analyze the socio-residential factors associated with extremely and very preterm deliveries occurring in non-level 3 maternity units in France.

MATERIALS AND METHODS

This is a population-based observational retrospective study using national hospital data from 2012 to 2014. A generalized estimating equations regression model was used to study the characteristics of women who delivered very preterm and the socio-residential risk factors for not delivering in a level 3 maternity unit at 24-31+6d weeks of gestation.

RESULTS

Among deliveries resulting in live births and without contraindication to in-utero transfer, we identified 9198 extremely or very preterm deliveries; 2122 (23.1%) of these were managed in a non-level 3 unit. Our study showed that young maternal age (women under 20 years at delivery) was associated with the risk of giving birth prematurely in a non-level 3 maternity, and particularly in a level 1 maternity unit (adjusted relative risk, 1.53; 95% CI 1.09-2.16). Living more than 30 minutes away from the closest level 3 unit increased the risk of delivering very preterm in a level 1 or 2 unit. Living in an urban area or urban periphery increased the risk of giving birth in a level 2 maternity unit (adjusted relative risk, 1.53; 95% CI 1.28-1.83 and 1.42; 95% CI 1.17-1.71, respectively).

CONCLUSION

This study shows that young pregnant women living more than 30 minutes from a level 3 hospital have an increased risk of delivering in a maternity unit that is not equipped to deal with premature births. The risk also increases with an urban place of residence when the delivery occurs in a level 2 unit. A clearer understanding of the population at risk of delivering prematurely in a non-level 3 maternity could lead to improvements in structuring healthcare to encourage earlier management and better support.

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.

Paternal country of origin and adverse neonatal outcomes in births to foreign-born women in Norway: A population-based cohort study

BACKGROUND

Migration is a risk factor for adverse neonatal outcomes. The various impacts of maternal origin have been reported previously. The aim of this study was to investigate associations between paternal origin and adverse neonatal outcomes in births to migrant and Norwegian-born women in Norway.

METHODS AND FINDINGS

This nationwide population-based study included births to migrant (n = 240,759, mean age 29.6 years [±5.3 SD]) and Norwegian-born women (n = 1,232,327, mean age 29.0 years [±5.1 SD]) giving birth in Norway in 1990-2016. The main exposure was paternal origin (Norwegian-born, foreign-born, or unregistered). Neonatal outcomes were very preterm birth (22+0-31+6 gestational weeks), moderately preterm birth (32+0-36+6 gestational weeks), small for gestational age (SGA), low Apgar score (<7 at 5 minutes), and stillbirth. Associations were investigated in migrant and Norwegian-born women separately using multiple logistic regression and reported as adjusted odds ratios (aORs) with 95% confidence intervals (CIs), adjusted for year of birth, parity, maternal and paternal age, marital status, maternal education, and mother's gross income. In births to migrant women, a foreign-born father was associated with increased odds of very preterm birth (1.1% versus 0.9%, aOR 1.20; CI 1.08-1.33, p = 0.001), SGA (13.4% versus 9.5%, aOR 1.48; CI 1.43-1.53, p < 0.001), low Apgar score (1.7% versus 1.5%, aOR 1.14; CI 1.05-1.23, p = 0.001), and stillbirth (0.5% versus 0.3%, aOR 1.26; CI 1.08-1.48, p = 0.004) compared with a Norwegian-born father. In Norwegian-born women, a foreign-born father was associated with increased odds of SGA (9.3% versus 8.1%, aOR 1.13; CI 1.09-1.16, p < 0.001) and decreased odds of moderately preterm birth (4.3% versus 4.4%, aOR 0.95; CI 0.91-0.99, p = 0.015) when compared with a Norwegian-born father. In migrant women, unregistered paternal origin was associated with increased odds of very preterm birth (2.2% versus 0.9%, aOR 2.29; CI 1.97-2.66, p < 0.001), moderately preterm birth (5.6% versus 4.7%, aOR 1.15; CI 1.06-1.25, p = 0.001), SGA (13.0% versus 9.5%, aOR 1.50; CI 1.42-1.58, p < 0.001), low Apgar score (3.4% versus 1.5%, aOR 2.23; CI 1.99-2.50, p < 0.001), and stillbirth (1.5% versus 0.3%, aOR 4.87; CI 3.98-5.96, p < 0.001) compared with a Norwegian-born father. In Norwegian-born women, unregistered paternal origin was associated with increased odds of very preterm birth (4.6% versus 1.0%, aOR 4.39; CI 4.05-4.76, p < 0.001), moderately preterm birth (7.8% versus 4.4%, aOR 1.62; CI 1.53-1.71, p < 0.001), SGA (11.4% versus 8.1%, aOR 1.30; CI 1.24-1.36, p < 0.001), low Apgar score (4.6% versus 1.3%, aOR 3.51; CI 3.26-3.78, p < 0.001), and stillbirth (3.2% versus 0.4%, aOR 9.00; CI 8.15-9.93, p < 0.001) compared with births with a Norwegian-born father. The main limitations of this study were the restricted access to paternal demographics and inability to account for all lifestyle factors.

CONCLUSION

We found that a foreign-born father was associated with adverse neonatal outcomes among births to migrant women, but to a lesser degree among births to nonmigrant women, when compared with a Norwegian-born father. Unregistered paternal origin was associated with higher odds of adverse neonatal outcomes in births to both migrant and nonmigrant women when compared with Norwegian-born fathers. Increased attention to paternal origin may help identify women in maternity care at risk for adverse neonatal outcomes.

Perinatal health of refugee and asylum-seeking women in Sweden 2014-17: a register-based cohort study

Background

An increasing number of migrants have fled armed conflict, persecution and deteriorating living conditions, many of whom have also endured risky migration journeys to reach Europe. Despite this, little is known about the perinatal health of migrant women who are particularly vulnerable, such as refugees, asylum-seekers, and undocumented migrants, and their access to perinatal care in the host country.

Methods

Using the Swedish Pregnancy Register, we analyzed indicators of perinatal health and health care usage in 31 897 migrant women from the top five refugee countries of origin between 2014 and 2017. We also compared them to native-born Swedish women.

Results

Compared to Swedish-born women, migrant women from Syria, Iraq, Somali, Eritrea and Afghanistan had higher risks of poor self-rated health, gestational diabetes, stillbirth and infants with low birthweight. Within the migrant population, asylum-seekers and undocumented migrants had a higher risk of poor maternal self-rated health than refugee women with residency, with an adjusted risk ratio (RR) of 1.84 and 95% confidence interval (95% CI) of 1.72–1.97. They also had a higher risk of preterm birth (RR 1.47, 95% CI 1.21–1.79), inadequate antenatal care (RR 2.56, 95% CI 2.27–2.89) and missed postpartum care visits (RR 1.15, 95% CI 1.10–1.22).

Conclusion

Refugee, asylum-seeking and undocumented migrant women were vulnerable during pregnancy and childbirth. Living without residence permits negatively affected self-rated health, pregnancy and birth outcomes in asylum-seekers and undocumented migrants. Pregnant migrant women’s special needs should be addressed by those involved in the asylum reception process and by health care providers.

Perinatal health among foreign versus native-born mothers in Canada: variations across outcomes and cohorts

BACKGROUND

To examine perinatal health differences between foreign-born and native-born mothers in Canada across multiple outcomes and two cohorts 10 years apart.

METHODS

Using 94 896 and 131 271 births in the 1996 and 2006 Canadian Census-Birth Cohort, respectively, we estimated risk ratios and risk differences of preterm birth (PTB), small-for-gestational age (SGA), large-for-gestational age (LGA), stillbirth and infant mortality between foreign-born and Canadian-born mothers.

RESULTS

In the 1996 cohort, we observed no important differences in adverse outcomes between foreign-born and native-born mothers. In the 2006 cohort, however, foreign-born mothers had lower risks of PTB, LGA, stillbirth, and infant mortality and a higher risk of SGA on both the relative and absolute scales. Lowered risk of PTB among foreign-born mothers in the 2006 cohort was also observed within Caucasian, East Asian, Southeast Asian and South Asian mothers. Favourable outcomes associated with foreign-born status in the 2006 cohort were negatively graded by duration of residence in Canada among immigrant mothers.

CONCLUSIONS

Differences in perinatal health by maternal foreign-born status varied across cohorts and a more pronounced 'healthy migrant' effect was observed among more recent migrants. The native-born mothers' perinatal health over time and a more restrictive/selective immigration policy in recent years would explain our results.

Differences in caesarean delivery and neonatal outcomes among women of migrant origin in Finland: A population-based study

BACKGROUND

In Finland, limited information is available on neonatal disparities among women of migrant origin.

OBJECTIVE

This study investigated differences in caesarean delivery and neonatal outcomes between women of migrant origin and Finnish women in Finland.

METHODS

The study was based on nationwide data from the Medical Birth Register of Finland. Our study included information on the most recent singleton birth of women delivering between January 2004 and December 2014 (N = 382 233). Women were classified into nine regional categories based on their country of origin. Generalized linear models were used to describe associations between country of origin and pregnancy outcomes adjusted for maternal age, socio-economic status, pre-pregnancy body mass index, parity, marital status, smoking during pregnancy, and delivery year. Finnish women were the reference group.

RESULTS

Among the study population, almost 92% of women were of Finnish origin; the remaining 8% were of migrant origin. Among the migrant women, those of Russian/former USSR origin were the largest group (n = 11 994); the smallest group was women of Latin American/Caribbean origin (n = 739). Compared with Finnish women, women of sub-Saharan African, South Asian, and East Asian origin were at greater risk of emergency caesarean delivery, preterm birth, low birthweight, and lower five-minute Apgar scores for newborns. Latin American/Caribbean-origin women were at increased risk of both elective and emergency caesarean delivery and lower five-minute Apgar scores compared with Finnish women. Women of Russian/former USSR origin overall had a lower risk of caesarean delivery and poor neonatal outcomes compared with Finnish women.

CONCLUSIONS

We identified sub-Saharan African, South Asian, and East Asian women as higher-risk groups, and women from Russia/former USSR as a lower-risk group, for emergency caesarean delivery and poor neonatal outcome compared with Finnish women. More research is needed to identify the reasons for these differences by country of origin in Finland.

2009 IOM guidelines for gestational weight gain: how well do they predict outcomes across ethnic groups?

Objective: To determine whether the Institute Of Medicine's (IOM) 2009 guidelines for weight-gain during pregnancy are predictive of maternal and infant outcomes in ethnic minority populations.Methods: We designed a population-based study using administrative data on 181,948 women who delivered live singleton births in Washington State between 2006-2008. We examined risks of gestational hypertension, preeclampsia/eclampsia, cesarean delivery, and extended hospital stay in White, Black, Native-American, East-Asian, Hispanic, South-Asian and Hawaiian/Pacific islander women according to whether they gained more or less weight during pregnancy than recommended by IOM guidelines. We also examined risks of neonatal outcomes including Apgar score <7 at 5 min, admission to NICU, requirement for ventilation, and a diagnosis of small or large for gestational age at birth.Results: Gaining too much weight was associated with increased odds for gestational hypertension (adjusted OR (aOR) ranged between 1.53-2.22), preeclampsia/eclampsia (aOR 1.44-1.81), cesarean delivery (aOR 1.07-1.38) and extended hospital stay (aOR 1.06-1.28) in all ethnic groups. Gaining too little weight was associated with decreased odds for gestational hypertension and delivery by cesarean section in Whites, Blacks and Hispanics. Gaining less weight or more weight than recommended was associated with increased odds for small for gestational age and large for gestational age infants respectively, in all ethnic groups.Conclusions: Adherence to the 2009 IOM guidelines for weight gain during pregnancy reduces risk for various adverse maternal outcomes in all ethnic groups studied. However, the guidelines were less predictive of infant outcomes with the exception of small and large for gestational age.Abbreviations: GWG: Gestational weight gain; IOM/NRC; Institute of Medicine and National Research Council; NICU: Neonatal intensive care need for ventilation; SGA: Small for gestational age; LGA: Large for gestational age; BERD: Birth Events Records Database; CHARS: Comprehensive Hospital Discharge Abstract Reporting System; ICD: International Classification of Disease; LMP: Last menstrual period; OR: Odds ratio.

Ethnic differences in singleton preterm birth in England and Wales, 2006-12: Analysis of national routinely collected data

BACKGROUND

Data recorded at birth and death registration in England and Wales have been routinely linked with data recorded at birth notification since 2006. These provide scope for detailed analyses on ethnic differences in preterm birth (PTB).

OBJECTIVES

We aimed to investigate ethnic differences in PTB and degree of prematurity in England and Wales, taking into account maternal sociodemographic characteristics and to further explore the contribution of mother's country of birth to these ethnic differences in PTB.

METHODS

We analysed PTB and degree of prematurity by ethnic group, using routinely collected and linked data for all singleton live births in England and Wales, 2006-2012. Logistic regression was used to adjust for mother's age, marital status/registration type, area deprivation and mother's country of birth.

RESULTS

In the 4 634 932 births analysed, all minority ethnic groups except 'Other White' had significantly higher odds of PTB compared with White British babies (ORs between 1.04-1.25); highest odds were in Black Caribbean, Indian, Bangladeshi and Pakistani groups. Ethnic differences in PTB tended to be greater at earlier gestational ages. In all ethnic groups, odds of PTB were lower for babies whose mothers were born outside the UK.

CONCLUSIONS

In England and Wales, Black Caribbean, Indian, Bangladeshi, Pakistani and Black African babies all have significantly increased odds of being born preterm compared with White British babies. Bangladeshis apart, these groups are particularly at risk of extremely PTB. In all ethnic groups, the odds of PTB are lower for babies whose mothers were born outside the UK. These ethnic differences do not appear to be wholly explained by area deprivation or other sociodemographic characteristics.

Maternal and infant pregnancy outcomes in women with psoriatic arthritis: a Swedish nationwide cohort study

OBJECTIVE

Studies on pregnancy outcomes in psoriatic arthritis (PsA) are scarce and typically of small size. Available studies have reported conflicting results. The aim of this study was to describe maternal and infant pregnancy outcomes among women with PsA compared with women without PsA.

DESIGN

Nationwide cohort study.

SETTING

Nationwide Swedish registers.

POPULATION

A total of 41 485 singleton pregnancies in 1997-2014, of which 541 pregnancies were identified with PsA exposure and 40 944 pregnancies were unexposed.

METHODS

By linkage of national health and population register data, we obtained information on individual pregnancies and compared outcomes among pregnancies with PsA and non-PsA pregnancies. Relative risks were estimated by odds ratios (ORs) with 95% CIs using a generalised linear regression model with generalised estimating equations. Adjustments were made for maternal factors and calendar year of birth.

MAIN OUTCOME MEASURES

Maternal and infant pregnancy outcomes.

RESULTS

Pregnancies to women with PsA had increased risks of preterm birth (adjusted OR 1.63; 95% CI 1.17-2.28), elective and emergency caesarean deliveries (adjusted OR 1.47; 95% CI 1.10-1.97 and adjusted OR 1.43; 95% CI 1.08-1.88, respectively) compared with non-PsA pregnancies. No increased risks were observed for pre-eclampsia, stillbirth or other infant outcomes apart from preterm birth.

CONCLUSION

The majority of women with PsA have uneventful pregnancies with respect to adverse outcomes. In the present study, we found increased risks of preterm birth and caesarean delivery compared with non-PsA pregnancies.

TWEETABLE ABSTRACT

Women with psoriatic arthritis have uneventful pregnancies but are at increased risk of preterm birth and caesarean delivery.

Birth outcomes of immigrant women married to native men in the Republic of Korea: a population register-based study

OBJECTIVES

The Republic of Korea (Korea) has experienced a steady increase in the number of births from immigrant women over the last 20 years. However, little is known about the birth outcomes of immigrant women in Korea. This study compared Korean birth data from immigrant and native women who married native men, and explored the factors that affected birth outcomes among immigrant women.

DESIGN

Observational cross-sectional study.

SETTING

Nationwide registry-based study in Korea.

PARTICIPANTS

A total of 70 258 records from immigrant women and 1700 976 records from native women were examined using the National Birth Registration Database, from 2010 to 2013.

INDEPENDENT VARIABLE

Native Korean women and immigrant women who married native men.

OUTCOMES

Proportion of preterm births, post-term births, low birth weights and macrosomia.

RESULTS

Adjusted ORs (aOR) were calculated for the adverse birth outcomes, and subgroup analyses were performed according to parity and mothers from three Asian countries (China, Vietnam, the Philippines). Multivariate logistic regression analyses were also conducted to evaluate the association of these factors with birth outcomes among immigrant women. Immigrant women had higher OR of post-term births (aOR 1.62; 95% CI 1.44 to 1.83) and low birth weights (aOR 1.17; CI 1.12 to 1.22). Mothers from the Philippines had higher OR of preterm births (aOR 1.26; CI 1.12 to 1.52) and Chinese mothers had higher OR of macrosomia (aOR 1.55; CI 1.44 to 1.66). The OR of post-term births and low birth weights was significantly higher in the first pregnancies of immigrant women.

CONCLUSIONS

This study has demonstrated higher proportions of adverse birth outcomes among immigrant women who married Korean men, compared with native women in Korea. Policies reducing the gap in birth outcomes between native and immigrant women are needed.

Risk factors for intrapartum acidemia - a cohort study

PURPOSE

Birth acidemia is associated with short- and long-term morbidity in the child. Optimal intrapartum surveillance and timely interventions may reduce the incidence of these outcomes. Knowledge about conditions which increase the risks might be beneficial for optimal care. The aim with this study was to identify factors which increased the risk for lactacidemia in fetal scalp blood.

MATERIALS AND METHODS

A secondary analysis of a cohort study performed at Karolinska University Hospital Stockholm Sweden between February 2009 and February 2011. The study population included 1070 women in labor where fetal scalp blood sampling (FBS) was performed.

RESULTS

In a univariate logistic regression analysis for lactate >4.8 mmol/L at FBS, minor language barriers (OR 2.54; 95%CI 1.26-5.11), active bearing down (OR 2.46; 95%CI 1.12-5.39) and maternal height <155 cm (OR 2.15; 95%CI 1.08-4.26) were found as risk factors. In a multivariate logistic regression analysis, minor language barriers (OR 2.21; 95%CI 1.05-4.67) and active pushing (OR 2.68; 95%CI 1.20-6.00) remained significant.

CONCLUSIONS

Language barriers, active pushing and short stature were found to be significant risk factors for intrapartum lactacidemia. In the group with minor language problems better use of interpreters might be beneficial.

Ethnic Disparities in Dental Caries among Six-Year-Old Children in the Netherlands

The aim of this study was to investigate potential differences in caries prevalence of children from ethnic minority groups compared to native Dutch children and the influence of socio-economic status (SES) and parent-reported oral health behaviour on this association. The study had a cross-sectional design, embedded in a population-based prospective multi-ethnic cohort study. 4,306 children with information on caries experience, belonging to 7 different ethnic groups, participated in this study. The decayed, missing, and filled teeth (dmft) index was assessed at the age of 6 and categorized in two ways for analysis: children without caries (dmft = 0) versus any caries experience (dmft >0) and children without caries (dmft = 0) versus children with mild caries (dmft = 1-3) or severe caries (dmft >3). Compared to native Dutch children, children with a Surinamese-Hindustani, Surinamese-Creole, Turkish, Moroccan, and Cape Verdean background had significantly higher odds for dental caries. Especially the Surinamese-Hindustani, Turkish, and Moroccan group had significantly higher odds for severe dental caries. Household income and educational level of the mother explained up to 43% of the association between ethnicity and dental caries, whereas parent-reported oral health behaviour did not mediate the association. Alarming disparities in caries prevalence between different ethnic (minority) groups exist, which cannot be fully explained by social inequalities. Public health strategies can apply this new knowledge and specifically focus on the reduction of ethnic disparities in oral health. More research is needed to explain the high caries prevalence among different ethnic minority groups.

Socio-economic risk factors for preterm birth in Norway 1999–2009

Aims: Preterm birth is a major cause of perinatal mortality and morbidity and is strongly associated with socio-economic factors. The objective of this study was to examine the associations of maternal education, marital status and ethnicity with preterm birth and to determine the extent to which such associations can be explained by the established risk factors of maternal age, parity and smoking. Methods: This was a register-based cohort study with data from the Medical Birth Registry of Norway 1999–2009 and Statistics Norway. The sample included all singleton spontaneous births in Norway from 1999 to 2009 ( n=494,073). The main outcome measure was preterm birth (gestational age <37 weeks). Results: Low maternal education and single motherhood were associated with preterm birth. After adjustment for the established risk factors, the excess risks were reduced, but remained statistically significant. The relative risk for low education was reduced from 1.50 to 1.36 and for single motherhood from 1.50 to 1.28. Women from Asia had a higher risk of preterm birth than Norwegian-born women (relative risk 1.29) with minor effects of adjustment. Conclusions: Several socio-economic risk factors are associated with preterm birth in Norway. In addition to the established risk factors, prenatal health care should focus on high-risk groups defined by maternal education, marital status and ethnicity.