The obstetric performance of Chinese immigrants residing in the UK

Salmon Bias and Preterm Birth Among Western Immigrants in China

Introduction Immigrants from Western industrialized countries are rarely found in immigrant studies. Our primary objective was to calculate the rate of cesarean delivery, 5-min Apgar score <7, and preterm birth among Chinese and Western women. Our secondary objective was to examine whether there are significant differences in terms of risk factors between Western immigrants who chose to deliver in their country of citizenship compared to those who chose to deliver in China. Methods Single-center retrospective cohort study in Shanghai, China. Multivariate logistic regression models used delivery outcome, and place of delivery (China vs. country of citizenship) as outcome variables. Results Preterm birth occurred at a rate of 3.82% among Chinese citizens, 4.12% among Chinese-born Western citizens, and 6.54% among non-Chinese-born Western citizens. After adjustment, preterm birth <37 weeks was more frequent among non-Chinese-born Western citizens compared with Chinese citizens, with an odds ratio of 1.82 (Confidence Interval 1.20-2.78), p = 0.005. Variables statistically associated with giving birth in China were maternal age ≥35 years and being Chinese-born Western, as well as the absence of medical or obstetrical conditions. Discussion Western immigrants have overall good obstetrical outcomes in China, and this could be partly explained by selective immigration, but also by the Salmon bias, as women with risk factors tend to return to their country of citizenship for the delivery. However, the preterm birth rate was higher among Western women than in their Chinese counterparts, and further research is needed.

Differences between native and immigrant women in Taiwan in factors associated with caesarean section: A prospective observational study

This study aimed to examine the association of social support, social factors, and maternal complications with caesarean deliveries in native and immigrant women, and to explore the association between acculturation and caesarean deliveries in immigrant women in Taiwan. This prospective panel study was conducted from August 2012 through April 2014 and included 222 native and 147 immigrant pregnant women in Taiwan. Caesarean rates did not differ significantly between native and immigrant women, including the overall caesarean rate (28.8%, 32.0%), medically indicated caesarean (22.5%, 24.5%), and caesarean without medical indications (6.3%, 7.5%). Results of multiple logistic regression models revealed that maternal complications and household activity support were positively associated with caesarean deliveries. Both native and immigrant women with high levels of informational support were less likely to receive caesareans. Immigrant women who were older than 35 years, had a middle level socioeconomic status, and perceived a high level of acceptance of caesarean in Taiwan were more likely to have caesarean deliveries. Informational support was a protective factor for caesarean delivery, whereas household activity support offered by the family was positively associated with caesarean delivery. Perceived acceptance level in mainstream society could affect immigrant women's use of caesarean delivery.

Maternal mortality and severe morbidity in a migration perspective

Among migrants in high-income countries, maternal mortality and severe morbidity generally occur more frequently as compared to host populations. There is marked variation between groups of migrants and host countries, with much elevated risks in some groups and no elevated risk at all in others. Those without a legal resident permit are most vulnerable. A reason for these elevated risks could be a different risk profile in migrants, but risk factors are unevenly distributed and not always present. Another reason is substandard care, which is identified more frequently in migrants, and comprises patient delays, for example, due to a lack of knowledge about the health system in the host country, and health worker delays, often compounded by communication barriers. Improvements in family planning and antenatal services are needed, and audits and confidential enquiries should be extended to include maternal morbidity and ethnic background. This requires scientific and political efforts.

Pregnancy outcomes in women greater than 45 years: a cohort control study in a multi-ethnic inner city population

OBJECTIVE

To examine the pregnancy outcomes of women >45 years in a multi-ethnic population when compared to controls and to reflect on socio-demographic details of the older mothers.

DESIGN

A retrospective cohort control study over an 8-year period in an inner city London hospital with multi-ethnic population. The influence of advanced maternal age (>45 years at time of delivery) on fetal and maternal outcomes was assessed by comparing these women to controls (aged 20-30 years) matched for ethnicity, country of origin and parity.

RESULTS

Data from 64 cases and 64 controls were compared. Ninety percent of the index group had undergone assisted conception. Mothers >45 years had a fourfold increase in cesarean section (35/64 vs 8/64), a threefold increase in blood loss (669.2 vs 272.4 ml) (both p < 0.001) and were more likely to have preterm birth (12/64 vs 3/64) (p < 0.05). Only 5 % of the 64 women were born in the United Kingdom, 52 % were unemployed and 50 % were not fluent in English. Seventy-five percent of the study population were multiparous, 52 % of the pregnancies were unplanned and 90 % had conceived spontaneously.

CONCLUSION

In an inner city immigrant population, older mothers >45 years were more likely to have cesarean sections, postpartum hemorrhage and premature deliveries. Moreover, social and demographic factors suggest that late child bearing is influenced by cultural factors such as acceptance of large families and lack of contraception.

Obstetric outcome of ethnic Turkish women in London: a retrospective case-control study

There is concern that the maternal mortality in ethnic minority women is significantly greater than that of Caucasian British women. The objective of this study was to compare the demographic and obstetric outcomes between these two groups. Data were collected retrospectively over a 2-year period from 148 index and 148 control cases. The study group had statistically similar maternal age, labour duration, blood loss and mode of delivery compared with Caucasian British women (p > 0.05). A total of 68% of Turkish women spoke little or no English; were more likely to be non-smokers and also more likely to be married to unemployed spouses (p = 0.0001). This is the first study comparing obstetric outcomes of immigrant Turkish women with their Caucasian British counterparts. There was no significant difference in maternal or fetal outcomes, which could be attributed to the 'healthy migrant' theory, coupled with increased vigilance in ethnic minority pregnancies.

International migration and caesarean birth: a systematic review and meta-analysis

Background

Perinatal health disparities including disparities in caesarean births have been observed between migrant and non-migrant women and some literature suggests that non-medical factors may be implicated. A systematic review was conducted to determine if migrants in Western industrialized countries consistently have different rates of caesarean than receiving-country-born women and to identify the reasons that explain these differences.

Methods

Reports were identified by searching 12 literature databases (from inception to January 2012; no language limits) and the web, by bibliographic citation hand-searches and through key informants. Studies that compared caesarean rates between international migrants and non-migrants living in industrialized countries and that did not have a ‘fatal flaw’ according to the US Preventative Services Task Force criteria were included. Studies were summarized, analyzed descriptively and where possible, meta-analyzed.

Results

Seventy-six studies met inclusion criteria. Caesarean rates between migrants and non-migrants differed in 69% of studies. Meta-analyses revealed consistently higher overall caesarean rates for Sub-Saharan African, Somali and South Asian women; higher emergency rates for North African/West Asian and Latin American women; and lower overall rates for Eastern European and Vietnamese women. Evidence to explain the consistently different rates was limited. Frequently postulated risk factors for caesarean included: language/communication barriers, low SES, poor maternal health, GDM/high BMI, feto-pelvic disproportion, and inadequate prenatal care. Suggested protective factors included: a healthy immigrant effect, preference for a vaginal birth, a healthier lifestyle, younger mothers and the use of fewer interventions during childbirth.

Conclusion

Certain groups of international migrants consistently have different caesarean rates than receiving-country-born women. There is insufficient evidence to explain the observed differences.