Obstetric profiles and pregnancy outcomes of immigrant women in New South Wales, 1990-1992

Exploring causal mechanisms of psychosis risk

Robust epidemiological evidence of risk and protective factors for psychosis is essential to inform preventive interventions. Previous evidence syntheses have classified these risk and protective factors according to their strength of association with psychosis. In this critical review we appraise the distinct and overlapping mechanisms of 25 key environmental risk factors for psychosis, and link these to mechanistic pathways that may contribute to neurochemical alterations hypothesised to underlie psychotic symptoms. We then discuss the implications of our findings for future research, specifically considering interactions between factors, exploring universal and subgroup-specific factors, improving understanding of temporality and risk dynamics, standardising operationalisation and measurement of risk and protective factors, and developing preventive interventions targeting risk and protective factors.

The effect of hepatitis B virus on the risk of pregnancy outcomes: a systematic review and meta-analysis of cohort studies

BACKGROUND

The effect of HBV on neonatal and maternal outcomes can create a basis for more accurate clinical decision-making. So, the aim of this meta-analysis is to detrmine the effect of chronic hepatitis B virus on the risk of pregnancy outcomes by combining cohort studies.

METHODS

International databases in this meta-analysis included the Cumulated Index to Nursing and Allied Health Literature (CINAHL), SPORT Discuss via the EBSCO interface, PubMed (Medline), Scopus, Web of Science, Embase, which were searched up to April 2023. All cohort studies reporting the risk ratio (RR) with a 95% confidence interval (CI) were included in the study. The quality assessment was done based on the Newcastle-Ottawa Scale (NOS).

RESULTS

Finally, thirty-five cohort studies were selected for meta-analysis. Outcomes of interest included pre-eclampsia, gestational diabetes, abortion, preterm birth, infant death, and other related outcomes. Results showed that the pooled RR for incident gestational diabetes in pregnant women with choronic hepatitis B infection was 1.16 (RR: 1.16; 95% CI 1.13-1.18; I-square: 92.89%; P value: 0.00). Similarly, the association between the presence of hepatitis B infection in pregnant women and the occurrence of pre-eclampsia was 1.10 (RR: 1.10; 95% CI 1.04-1.16; I-square: 92.06%; P value: 0.00). The risk of preterm delivery in pregnant women with hepatitis B infection was 1.17 times that of pregnant women without hepatitis B infection (RR: 1.17; 95% CI 1.14-1.20; I-squared: 94.32%; P value: 0.00).

CONCLUSION

This meta-analysis found that hepatitis B infection during pregnancy may be associated with an increased risk of gestational diabetes, preterm delivery, pre-eclampsia, and eclampsia. However, confirmation of this association, as well as the specific biological pathways involved in the association between HBV infection and pregnancy outcomes, requires further investigation.

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.

Maternal Asian ethnicity and obstetric intrapartum intervention: a retrospective cohort study

BACKGROUND

Maternal ethnicity is a recognized risk factor for stillbirth, such that South Asian women have higher rates than their Caucasian counterparts. However, whether maternal ethnicity is a risk factor for intrapartum outcomes is less clear. The aim of this study is to explore associations between maternal country of birth, operative vaginal delivery and emergency cesarean section, and to identify possible mechanisms underlying any such associations.

METHODS

We performed a retrospective cohort study of singleton term births among South Asian, South East/East Asian and Australian/New Zealand born women at an Australian tertiary hospital in 2009-2013. The association between maternal country of birth, operative vaginal birth and emergency cesarean was assessed using multivariate logistic regression.

RESULTS

Of the 31,932 births, 54% (17,149) were to Australian/New Zealand-born women, 25% (7874) to South Asian, and 22% (6879) to South East/East Asian born women. Compared to Australian/New Zealand women, South Asian and South East/East Asian women had an increased rate of both operative vaginal birth (OR 1.43 [1.30-1.57] and 1.22 [1.11-1.35] respectively, p < 0.001 for both) and emergency cesarean section (OR 1.67 [1.53-1.82] and 1.16 [1.04-1.26] respectively, p < 0.001 and p = 0.007 respectively). While prolonged labor was the predominant reason for cesarean section among Australian/New Zealand and South East/East Asian women, fetal compromise accounted for the majority of operative births in South Asian women.

CONCLUSION

South Asian and South East/East Asian women experience higher rates of both operative vaginal birth and cesarean section in comparison to Australian/New Zealand women, independent of other risk factors for intrapartum interventions.

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.

Socio-cultural disparities in GDM burden differ by maternal age at first delivery

AIMS

Several socio-cultural and biomedical risk factors for gestational diabetes mellitus (GDM) are modifiable. However, few studies globally have examined socio-cultural associations. To eliminate confounding of increased risk of diabetes in subsequent pregnancies, elucidating socio-cultural associations requires examination only of first pregnancies.

METHODS

Data for all women who delivered their first child in Victoria, Australia between 1999 and 2008 were extracted from the Victorian Perinatal Data Collection. Crude and adjusted GDM rates were calculated. Multivariate logistic regression was used to examine odds of GDM within and between socio-cultural groups.

RESULTS

From 1999 to 2008, 269,682 women delivered their first child in Victoria. GDM complicated 11,763 (4.4%) pregnancies and burden increased with maternal age, from 2.1% among women aged below 25 years at delivery to 7.0% among those aged 35 years or more. Among younger women, GDM rates were relatively stable across socioeconomic levels. Amongst older women GDM rates were highest in those living in most deprived areas, with a strong social gradient. Asian-born mothers had highest GDM rates. All migrant groups except women born in North-West Europe had higher odds of GDM than Australian-born non-Indigenous women. In all ethnic groups, these differences were not pronounced among younger mothers, but became increasingly apparent amongst older women.

CONCLUSIONS

Socio-cultural disparities in GDM burden differ by maternal age at first delivery. Socio-cultural gradients were not evident among younger women. Health and social programs should seek to reduce the risk amongst all older women to that of the least deprived older mothers.

The prevalence of pre-eclampsia in migrant relative to native Norwegian women: a population-based study

OBJECTIVE

To compare the prevalence of pre-eclampsia in migrant women with Norwegian women, and to study the prevalence of pre-eclampsia by length of residence in Norway.

DESIGN

Observational study.

SETTING

The Medical Birth Registry of Norway.

POPULATION

All Norwegian, Pakistani, Vietnamese, Somali, Sri Lankan, Filipino, Iraqi, Thai and Afghan women who gave birth after 20 weeks of gestation during the period 1986-2005 in Norway.

METHODS

The prevalence of pre-eclampsia was calculated by country of birth. The association of country of birth and length of residence in Norway with pre-eclampsia was estimated as the odds ratio (OR) with 95% confidence interval (CI), using Norwegian women as a reference. We made adjustments for maternal age, parity, multifetal pregnancy, year of delivery and maternal diabetes in multivariable analysis.

MAIN OUTCOME MEASURE

Pre-eclampsia.

RESULTS

Migrant women had a lower prevalence of pre-eclampsia than Norwegian women (2.7% versus 3.7%, P < 0.001). Vietnamese (OR, 0.36; CI, 0.29-0.45), Afghan (OR, 0.52; CI, 0.30-0.90) and Thai (OR, 0.57; CI, 0.45-0.73) women had the lowest risk of pre-eclampsia relative to Norwegian women. Adjustment for the variables above or separate analyses for nulliparous women did not change the estimates notably. Using Norwegian women as the reference, the risk of pre-eclampsia increased by length of residence for migrant women: adjusted OR of 0.64 (0.59-0.70) at <5 years and 0.91 (0.84-0.99) at ≥5 years of residence.

CONCLUSIONS

The risk of pre-eclampsia was lower in migrants relative to Norwegian women, but increased by length of residence in Norway.

Seeking maternal care at times of conflict: the case of Lebanon

Providing quality maternity care within the emergency care packages for internally displaced populations in war-affected areas is somewhat challenging, although very essential. In this retrospective study, we describe the experiences and health care seeking behaviors of 1,015 pregnant and postpartum women during the 2006 war in Lebanon. Women reported interruptions in regular maternity care and experienced more complications during this period. Availability of health services and experiences of complications were the most important determinants of health care seeking behaviors. Maternal health services should be a part of any comprehensive emergency responsiveness plan, catering to women's needs in war-affected areas.

Maternal hepatitis B surface antigen status and incidence of pre-eclampsia

The relationship between chronic hepatitis B virus (HBV) infection with atherosclerosis and cardiovascular disorders remains unclear, and the impact of maternal HBV infection on the development of pregnancy-induced hypertension (PIH) and pre-eclampsia (PE) is also controversial. This retrospective cohort study was conducted to examine the relationship between maternal hepatitis B surface antigen (HBsAg) status with PIH and PE in singleton pregnancies that delivered at 24 weeks of gestation and beyond. Among the 86 537 cases in the cohort, 10% were HBsAg positive, and overall 2.0% had PIH, of whom 56.3% developed PE. HBsAg-positive women had higher weight and body mass index (BMI), but lower incidences of advanced age, nulliparity, PIH (1.6% vs 2.0%, P = 0.007) and PE (0.8% vs 1.1%, P = 0.005). On multiple logistic regression analysis adjusting for the effects of nulliparity, advanced age, high BMI, and underlying renal, cardiac and autoimmune diseases, HBsAg carriage was associated with significantly reduced incidence of PIH (aOR 0.79, 95% CI 0.66-0.95) and PE (aOR 0.71, 95% CI 0.56-0.91). Our results indicate that maternal HBsAg carriage is independently associated with reduced PE. As chronic HBV infection alters the immune response of the individual, our observation could be related to enhanced maternal immunotolerance of the foetus and hence a reduction in the incidence of PE. The implications of our findings on the long-term health outcome of the infected women, from cardiovascular morbidity to malignancies, warrant further studies.

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.

Maternal HBsAg status and infant size--a Faustian bargain?

Information on the impact of maternal hepatitis B virus (HBV) infection on pregnancy outcome is conflicting. Some studies reported an association with increased infant birthweight, which could be interpreted as advantageous to pregnancy. A retrospective study was performed to compare birthweight outcome between 6261 and 55,817 singleton pregnancies in mothers screened positive and negative for hepatitis B surface antigen (HBsAg), respectively. The HBsAg positive women were younger, had higher body mass index (BMI) and incidence of overweight, but less gestational weight gain, and were associated with increased macrosomia (birthweight ≥4000 g) in mothers <35 years (odds ratio, OR, 1.28), BMI ≥25 kg/m(2) (OR 1.24), without gestational diabetes mellitus (GDM, OR 1.19), and in male infants (OR 1.18). It was also associated with increased large-for-gestational age (LGA, birthweight >90th percentile) infants in nulliparas (OR 1.13), age <35 years (OR 1.12), BMI ≥25 kg/m(2) (OR 1.19), with (OR 1.36) and without (OR 1.09) GDM, and in male infants (OR 1.13). When the effects of high BMI, advanced age, GDM, and male infants were controlled for, positive HBsAg was significantly associated with macrosomic (adjusted odds ratio, aOR, 1.15) and LGA (aOR 1.11) infants. In view of the latest findings on the association between high infant birthweight with increased risk of obesity, diabetes mellitus, and various forms of malignancies from childhood to adulthood, further studies are warranted to determine if maternal hepatitis B infection would impact adversely on the long-term health of the offspring through its effect on increasing birthweight.

Breastfeeding initiation: is this influenced by maternal hepatitis B infection?

OBJECTIVE

To elucidate the effect of hepatitis B virus (HBV) infection on breastfeeding uptake in Chinese mothers in an endemic region.

PATIENTS AND METHODS

A retrospective cohort study on 63 885 consecutive pregnant delivered between January 1997 and June 2008, were extracted from computerized database to examine the relationship between breastfeeding uptake and maternal HBV status, adjusted for demographic factors.

RESULTS

A total of 6593 (10.3%) women were hepatitis B surface antigen (HBsAg)-positive, with an annual prevalence of around 10%. In the study period, 29 869 (46.8%) practised breastfeeding, and its prevalence ranged from 35.4 to 54.8% with an increasing trend throughout the years (p < 0.001). HBsAg-positive mothers had a significantly lower rate of breastfeeding (39.2 vs. 47.6% p < 0.001). Multiparas had higher incidence of HBV infection (10.9 vs. 9.8%, p < 0.001) and lower breastfeeding rate (42.2% versus 51.0%, p < 0.001) when compared with primiparas. Among those factors, maternal HBV infection had the strongest negative association with breastfeeding (adjusted odd ratio (aOR) = 0.726, 95% confidence interval (CI): 0.689-0.765).

CONCLUSIONS

Our results suggested maternal HBV infection was one of the factors for the persistently low breastfeeding rate in Hong Kong over the past decades. To promote breastfeeding, it is necessary to generate definitive data on its safety regarding to mother-to-child transmission (MTCT) of HBV in order to allay the fear and anxiety in HBsAg-positive mothers.

Maternal and neonatal outcomes associated with gestational diabetes in women from culturally and linguistically diverse backgrounds in Western Australia

AIMS

To compare maternal and neonatal outcomes for Australian-born women with gestational diabetes mellitus with those of culturally and linguistically diverse and non-culturally and linguistically diverse foreign-born women with gestational diabetes.

METHODS

A total of 205,616 singleton births in Western Australia between 1998 and 2006 were examined using multivariate logistic regression. Risks of ten maternal and neonatal outcomes associated with gestational diabetes were compared for pregnancies with gestational diabetes to foreign-born women from both culturally and linguistically diverse and non-culturally and linguistically diverse backgrounds vs. Australian-born women. The same outcomes were also compared for pregnancies without gestational diabetes.

RESULTS

Foreign-born culturally and linguistically diverse women were more likely to undergo emergency Caesarean section, but less likely to have pre-eclampsia, an elective Caesarean section or induced labour than Australian-born women. Their infants were less likely to be large for gestational age, require resuscitation or be transferred to specialist care. These differences were also evident among pregnancies without gestational diabetes to culturally and linguistically diverse women, but did not exist between foreign-born non-culturally and linguistically diverse women and Australian-born women with gestational diabetes.

CONCLUSIONS

While gestational diabetes places women and infants at increased risk of adverse perinatal outcomes, these outcomes differed for foreign-born women from culturally and linguistically diverse backgrounds when compared with Australian-born women. Further investigation is required to elucidate why being foreign-born and culturally and linguistically diverse reduces the risk of several of these outcomes.

Perinatal complications and cesarean delivery among foreign-born and Australian-born women in Western Australia, 1998-2006

OBJECTIVE

To determine whether common perinatal complications could explain variation in risk of cesarean among foreign-born and Australian-born women in Western Australia (WA).

METHODS

Complication prevalence was calculated using the linked records of 208 982 confinements to non-indigenous women in WA between 1998 and 2006. Logistic regression was used to estimate differences in risk of elective cesarean and emergency cesarean compared with vaginal delivery for foreign-born women from different regions.

RESULTS

The most common complications in emergency cesareans were failure to progress (36.7%) and fetal distress (35.7%). The most common complications in elective cesareans were previous cesarean (56.2%) and malpresentation (16.3%). Women from Sub-Saharan Africa, Southeast Asia, and Southern and Central Asia had an increased risk of emergency cesarean compared with Australian-born women (P<0.05), whereas women from Oceania, North Africa and the Middle East, and Northeast Asia had a decreased likelihood of elective cesarean compared with Australian-born women (P<0.05).

CONCLUSION

Complication prevalence varied by maternal region of birth. However, variation in these complications does not completely explain differences in mode of delivery among foreign-born and Australian-born women in WA. Sociocultural factors must be considered in future research and when establishing culturally appropriate guidelines for obstetric staff dealing with foreign-born women.

International migration and gestational diabetes mellitus: a systematic review of the literature and meta-analysis

Influxes of migrant women of childbearing age to receiving countries have made their perinatal health status a key priority for many governments. The international research collaboration Reproductive Outcomes And Migration (ROAM) reviewed published studies to assess whether migrants in countries of resettlement have a greater risk of gestational diabetes mellitus (GDM) than women in receiving countries. A systematic review of the literature from Medline, Embase, PsychInfo and CINAHL from 1990 to 2009 included studies of migrant women and GDM. Studies were excluded if there was no cross-border movement or comparison group or if the receiving country was not the country of resettlement. Studies were assessed for quality, analysed descriptively and meta-analysed. Twenty-four reports (representing >120,000 migrants) met our inclusion criteria. Migrants were described primarily by geographic origin; other relevant aspects (e.g. time in country, language fluency) were rarely studied. Migrants' results for GDM were worse than those for receiving-country women in 79% of all studies. Meta-analyses showed that, compared with receiving-country women, Caribbean, African, European and Northern European women were at greater risk of GDM, while North Africans and North Americans had risks similar to receiving-country women. Although results of the 31 comparisons of Asians, East Africans or non-Australian Oceanians were too heterogeneous to provide a single GDM risk estimate for migrant women, only one comparison was below the receiving-country comparison group, all others presented a higher risk estimate. The majority of women migrants to resettlement countries are at greater risk for GDM than women resident in receiving countries. Research using clear, specific migrant definitions, adjusting for relevant risk factors and including other aspects of migration experiences is needed to confirm and understand these findings.

Chronic hepatitis B virus infection and rubella susceptibility in pregnant women

Increased rubella susceptibility has been shown in subjects from the Asian-Pacific region where chronic hepatitis B virus (HBV) infection is endemic. This study was performed to explore the relationship between chronic HBV infection and rubella susceptibility in the obstetric population. We conducted a retrospective cohort study on 50556 pregnant women delivered in a university obstetric unit from January 1998 to June 2008. The incidence of rubella susceptibility according to maternal HBV carrier status was examined. HBV infection and rubella susceptibility were found in 5105 (10.1%) and 6102 (12.1%) women, respectively. Rubella susceptibility was more common in women with HBV (13.1%vs 12.0%, P = 0.017), even after adjusting for other confounding factors (odds ratio 1.11, 95% confidence interval 1.01-1.21). Advancing age was associated with progressively decreasing odds of rubella susceptibility, from 0.48 at age 20-24 years to 0.34 at age ≥ 40 years in women without HBV infection, but had no effect in women with hepatitis B. In conclusion, our study is the first to demonstrate an association between chronic HBV infection with rubella susceptibility. Further studies are warranted to confirm whether chronic HBV infection, especially that acquired by vertical transmission, may impair the immune response to rubella vaccine or natural infection throughout the reproductive age.

Implications of the relationship between maternal age and parity with hepatitis B carrier status in a high endemicity area

This study aimed to examine the prevalence of maternal hepatitis B virus (HBV) infection in the past 10 years and the age- and parity-specific incidences for evidence of control of HBV infection in the female reproductive population. We conducted a retrospective cohort study on 58 736 consecutive pregnant women delivered from July 1998 to June 2008. Maternal HBV status and demographic data were retrieved from a computerized database for analysis by year, age, year of birth and parity. A total of 5788 (10.1%) women had HBV infection, and the annual prevalence was around 10% throughout. When categorized by maternal age into six 5-year cohorts, the incidence increased from 6.8% in the <20 years cohort to 10.8% in the 20-24 and 25-29 year cohorts, then declined to 9.3% in the > or =40 years cohort (P < 0.001). When categorized by year of birth into 5-year cohorts, the incidence varied from 9.2% for the 1965-1969 cohort to 11.3% in the 1980-1984 cohort, which then declined to 7.3% in the > or =1985 cohort (P < 0.001). Multiparas had higher incidence when compared with nulliparas overall (10.5% vs 9.6%, P = 0.001), and significantly higher incidences for the 25-29 year (P = 0.009), 30-34 year (P < 0.001) and 35-39 year (P = 0.032) cohorts when analysed by age. In conclusion, the prevalence of maternal HBV infection remained constant at 10% for the past decade. The changes in relation to age and parity suggested that horizontal transmission, probably by sexual contact, had played an important role in maintaining the same prevalence as reported from Hong Kong 20 years ago.

Migration to western industrialised countries and perinatal health: a systematic review

Influxes of migrant women of childbearing age to receiving countries have made their perinatal health status a key priority for many governments. The international research collaboration Reproductive Outcomes And Migration (ROAM) reviewed published studies to assess whether migrants in western industrialised countries have consistently poorer perinatal health than receiving-country women. A systematic review of literature from Medline, Health Star, Embase and PsychInfo from 1995 to 2008 included studies of migrant women/infants related to pregnancy or birth. Studies were excluded if there was no cross-border movement or comparison group or if the receiving country was not western and industrialised. Studies were assessed for quality, analysed descriptively and meta-analysed when possible. We identified 133 reports (>20,000,000 migrants), only 23 of which could be meta-analysed. Migrants were described primarily by geographic origin; other relevant aspects (e.g., time in country, language fluency) were rarely studied. Migrants' results for preterm birth, low birthweight and health-promoting behaviour were as good or better as those for receiving-country women in >or=50% of all studies. Meta-analyses found that Asian, North African and sub-Saharan African migrants were at greater risk of feto-infant mortality than 'majority' receiving populations, and Asian and sub-Saharan African migrants at greater risk of preterm birth. The migration literature is extensive, but the heterogeneity of the study designs and definitions of migrants limits the conclusions that can be drawn. Research that uses clear, specific migrant definitions, adjusts for relevant risk factors and includes other aspects of migrant experience is needed to confirm and understand these associations.

Maternal hepatitis B infection and gestational diabetes mellitus

BACKGROUND/AIMS

This retrospective cohort study was performed to examine the relationship between maternal hepatitis B virus infection, as indicated by the surface antigen status, with the development of gestational diabetes mellitus in a normal-risk Chinese obstetric population.

METHODS

Maternal demographics, risk factors, and pregnancy outcome of 13,683 singleton pregnancies delivering in 1998-2001 were analysed according to maternal hepatitis B surface antigen status, which was routinely screened. Multiple logistic regression analysis was performed to examine the role of hepatitis B infection in the development of gestational diabetes mellitus.

RESULTS

The 1138 women (8.3%) with hepatitis B infection had lower mean weight and body mass index, similar prevalence of chronic medical diseases and smokers, but increased prevalence of gestational diabetes mellitus, which remained significant (odds ratio 1.24, 95% confidence interval 1.01-1.51) after adjustment for confounding variables. However, there was no difference in pregnancy outcome.

CONCLUSIONS

Our results confirmed the independent association between hepatitis B infection with gestational diabetes mellitus. The magnitude of chronic hepatitis B infection in the developing world and certain ethnic groups could have contributed to the high prevalence of gestational and possibly type 2 diabetes in these populations. Further studies on the long-term implications of our finding are warranted.

Pregnancy outcomes in foreign-born and US-born women

OBJECTIVES

To compare pregnancy outcomes between foreign-born women and women born in the United States (US-born).

METHODS

A retrospective cohort study (1991-2001) of all deliveries at Grady Memorial Hospital in Atlanta, Georgia.

RESULTS

Among 49,904 deliveries, 27% were to foreign-born mothers representing 164 countries grouped into eight geographic regions. Compared with US-born women, foreign-born women had a higher mean birthweight (3315 vs. 3083 g), and a lower risk of preterm delivery (RR 0.46, 95% CI 0.43-0.49), perinatal mortality (RR 0.40, 95% CI 0.36-0.45), hypertension (RR 0.31, 95% CI 0.23-0.41), and HIV infection (RR 0.13, 95% CI 0.10-0.18). However, foreign-born women had an increased risk of diabetes (RR 1.63, 95% CI 1.48-1.79), perineal laceration (RR 1.71; 95% CI 1.66-1.76), and postpartum hemorrhage (RR 1.10; 95% CI 1.05-1.15).

CONCLUSIONS

Foreign-born women have better health behaviors, pregnancy outcomes, and a lower risk of infectious diseases than US-born women, but they have a higher risk of certain medical conditions and obstetric complications.

Comparative analysis of pattern, management and outcome of pre- versus postnatally diagnosed major congenital heart disease: a population-based study

OBJECTIVES

Most pregnant women in New South Wales undergo obstetric ultrasound examination, including some assessment of fetal cardiac anatomy. We aimed to review the spectrum of cardiac defects, management and outcome data of all fetuses with diagnosis of major congenital heart disease between 1994 and 1996 and compare them to major congenital heart disease in infants born during the same 3-year study period.

METHODS

Descriptive comprehensive study of the New South Wales population. Study centers included the single fetal echocardiographic referral service and the two pediatric cardiac centers of New South Wales.

RESULTS

Ninety-seven fetuses and 562 infants with major congenital heart disease were identified (240,000 livebirths), resulting in a prenatal detection rate of 15%. Anomalies detectable by cardiac four-chamber views were diagnosed at an average rate of 30% (68/229) in utero. By contrast, lesions associated with abnormal ventricular outflow and great artery views were detected in only 6.7% (29/430; P < 0.0001) of cases prior to birth. Of the 97 fetuses, 29 were aborted, 16 died in utero, and 9 died early postnatally without treatment. Within 2 weeks of age, 23% with fetal and 40% (P < 0.05) with infant major congenital heart disease diagnosis required an intervention, mainly for patent ductus arteriosus dependent lesions. Postnatal survival was similar for the fetal and infant series up to 2 years of age: 77% (95% confidence interval 64-90%) vs. 85% (95% confidence interval 82-88%).

CONCLUSIONS

Prenatal diagnosis has important implications for pregnancy outcome, in particular for univentricular lesions. However, the present mode of obstetric routine ultrasound scanning fails to identify most ductus arteriosus dependent cardiac lesions with a predictable need for early postnatal intervention.

Obstetric profiles and perinatal mortality among Pacific Island immigrants in New South Wales, 1990-93

OBJECTIVES

To describe the obstetric profile and perinatal mortality of Pacific Island-born women giving birth in New South Wales (NSW) and assess risk factors associated with the high perinatal death rate previously noted in this immigrant group.

METHOD

Retrospective cohort study based on the Midwives Data Collection in NSW from 1990 to 1993. Births to 5,034 Pacific Island-born women were compared with births to 256,843 Australian-born women.

RESULTS

Pacific Island-born women had fewer teenage pregnancies and were of an older age and higher parity. They were more likely to be married or in a de facto relationship and to present for antenatal care later in the pregnancy. The proportion of low birthweight and preterm birth was similar in the two groups but Pacific Islanders had a higher perinatal mortality rate (14.6/1,000 vs. 10.3/1,000, RR = 1.42, 95% CI = 1.13-1.54). Even at normal and high birthweights, infants of Pacific Island-born women were at greater risk of perinatal death. After adjusting for maternal factors (marital status, insurance status, parity and maternal age) Pacific Islanders were 30% more likely to have a perinatal death (OR = 1.30, 95% CI 1.07-1.54).

CONCLUSIONS

Further analyses of the causes of perinatal death in Pacific Island-born women are needed so appropriate interventions can be implemented.

IMPLICATIONS

The need for the design and evaluation of culturally specific services aimed at improving antenatal care attendance in Pacific Islanders is emphasised. Conventional risk assessment may not adequately predict adverse perinatal outcomes in all populations.