Stillbirth rates among Haitians in Canada

Recent Advances in Placenta-Heart Interactions

Congenital heart defects (CHD) occur in ∼1 in every 100 live births. In addition, an estimated 10% of fetal loss is due to severe forms of CHD. This makes heart defects the most frequently occurring birth defect and single cause of in utero fatality in humans. There is considerable evidence that CHD is heritable, indicating a strong contribution from genetic risk factors. There are also known external environmental exposures that are significantly associated with risk for CHD. Hence, the majority of CHD cases have long been considered to be multifactorial, or generally caused by the confluence of several risk factors potentially from genetic, epigenetic, and environmental sources. Consequently, a specific cause can be very difficult to ascertain, although patterns of associations are very important to prevention. While highly protective of the fetus, the in utero environment is not immune to insult. As the conduit between the mother and fetus, the placenta plays an essential role in maintaining fetal health. Since it is not a fully-formed organ at the onset of pregnancy, the development of the placenta must keep pace with the growth of the fetus in order to fulfill its critical role during pregnancy. In fact, the placenta and the fetal heart actually develop in parallel, a phenomenon known as the placenta–heart axis. This leaves the developing heart particularly vulnerable to early placental insufficiency. Both organs share several developmental pathways, so they also share a common vulnerability to genetic defects. In this article we explore the coordinated development of the placenta and fetal heart and the implications for placental involvement in the etiology and pathogenesis of CHD.

Language and infant mortality in a large Canadian province

OBJECTIVES

Infant mortality in minority populations of Canada is poorly understood, despite evidence of ethnic inequality in other countries. We studied infant mortality in different linguistic groups of Quebec, and assessed how language and deprivation impacted rates over time.

STUDY DESIGN

Population-level study of vital statistics data for 1,985,287 live births and 10,283 infant deaths reported in Quebec from 1989 through 2012.

METHODS

We computed infant mortality rates for French, English, and foreign languages according to level of material deprivation. Using Kitagawa's method, we evaluated the impact of changes in mortality rates, and population distribution of language groups, on infant mortality in the province.

RESULTS

Infant mortality declined from 6.05 to 4.61 per 1000 between 1989-1994 and 2007-2012. Most of the decline was driven by Francophones who contributed 1.39 fewer deaths per 1000 births over time, and Anglophones of wealthy and middle socio-economic status who contributed 0.13 fewer deaths per 1000 births. The foreign language population and poor Anglophones contributed more births over time, including 0.08 and 0.02 more deaths per 1000 births, respectively. Mortality decreased for Francophones and Anglophones in each level of deprivation. Rates were lower for foreign languages, but increased over time, especially for the poor.

CONCLUSIONS

Infant mortality rates decreased for Francophones and Anglophones in Quebec, but increased for foreign languages. Poor Anglophones and individuals of foreign languages contributed more births over time, and slowed the decrease in infant mortality. Language may be useful for identifying inequality in infant mortality in multicultural nations.

Comparison of stillbirth rates by cause among Haitians and non-Haitians in Canada

OBJECTIVE

To compare rates of stillbirth among Haitians and non-Haitians in Canada.

METHODS

A retrospective cohort study was performed using data on all stillborn and live-born singletons weighing at least 500 g in the province of Quebec, Canada, from 1981 to 2010. Stillbirth rates were computed, and hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for Haitians relative to non-Haitians. The main outcome measure was stillbirth by cause of death.

RESULTS

Data for 9657 stillbirths (124 Haitian) and 2 414 751 live births (17 165 Haitian) were included. Stillbirth rates were higher for Haitians than non-Haitians (7.17 [95% CI 5.91-8.43] vs 3.96 [95% CI 3.88-4.04] per 1000 births), particularly for cord prolapse (adjusted HR 1.87, 95% CI 1.10-3.18) and placental abruption (adjusted HR 2.84, 95% CI 1.95-4.15). Haitians had higher risks of stillbirth due to cord prolapse and abruption at every week of pregnancy. Risks were not elevated for stillbirth due to congenital anomaly, a cause less responsive to urgent intervention.

CONCLUSION

Stillbirth rates among Haitians are disproportionately high in Canada, particularly fetal death due to cord prolapse and placental abruption. The potential to reduce stillbirth rates through optimal emergency care in vulnerable minorities requires further investigation.

Stillbirth in an Anglophone minority of Canada

OBJECTIVES

We assessed trends in stillbirth over time for Francophones and Anglophones of Quebec, a large Canadian province with publically funded health care and an English-speaking minority.

METHODS

We calculated stillbirth rates for Francophones and Anglophones, and estimated hazard ratios (HR) by decade from 1981 to 2010, adjusting for maternal characteristics. We analyzed temporal trends by gestational interval and cause of fetal death.

RESULTS

Stillbirth rates decreased in Quebec during the three decades, due to improved rates in Francophones. Rates decreased for Anglophones in 1991-2000, but increased in 2001-2010 at term, during the second trimester, and for most causes of fetal death. In the 2000s, the hazard of stillbirth for Anglophones was nearly the same as the hazard for Francophones in the 1980s (HR 0.93, 95 % confidence interval 0.82, 1.05).

CONCLUSIONS

Stillbirth rates declined in both Francophones and Anglophones before the turn of the century, but increased thereafter for Anglophones, suggesting that linguistic inequalities in stillbirth may be emerging in Quebec. Linguistic status may be a useful marker for surveillance of inequalities in stillbirth.