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Canadian Journal of Public Health

, Volume 104, Issue 2, pp e148–e153 | Cite as

Educational Inequality in Stillbirth: Temporal Trends in Québec From 1981 to 2009

  • Noémie Savard
  • Nathalie Auger
  • Alison L. Park
  • Ernest Lo
  • Jérôme Martinez
Quantitative Research

Abstract

OBJECTIVE: Educational inequality in stillbirth has been documented in high-income countries and the province of Québec, Canada, but temporal trends are poorly understood. Our objective was to determine time trends in inequality related to maternal education for all-cause and cause-specific stillbirth over the past three decades in Québec.

METHODS: We included 2,397,971 live births and 9,983 stillbirths from 1981 through 2009 using Québec vital statistics. For each decade, we computed measures of inequality capturing relative (relative index of inequality, RII) and absolute (slope index of inequality, SII) differences between the least- and most-educated mothers for all-cause and cause-specific stillbirth, adjusting for maternal characteristics.

RESULTS: Stillbirth rates decreased over time for all education levels. Absolute educational inequality (SII 2.5 per 1000 births, 95% CI 2.1–2.8; all periods combined) was stable over time, whereas relative inequality increased (RII1981–1989 1.8 vs. RII2000–2009 2.3). Absolute inequality decreased for stillbirths caused by placental abruption (SII1981–1989 0.6 vs. SII2000–2009 0.3), but increased for unspecified causes (SII1981–1989 0.2 vs. SII2000–2009 0.7).

CONCLUSIONS: Absolute educational inequality in stillbirth persisted and relative inequality increased over the past three decades, despite an overall decrease in stillbirth rates. The decrease in absolute inequality for placental abruption was countered by an increase for unspecified causes. A better understanding of the underlying components of unspecified causes is needed to further address educational inequality in stillbirth.

Key Words

Cause of death educational status fetal death socioeconomic factors stillbirth trend temporal 

Résumé

Objectif: Des inégalités de scolarité maternelle pour les mortinaissances ont été documentées dans plusieurs pays industrialisés, mais leurs tendances temporelles sont moins connues. Notre objectif était d’étudier les tendances temporelles des inégalités de scolarité pour les mortinaissances, toutes causes et par cause, pour les trois dernières décennies au Québec, Canada.

MÉTHODES: Nous avons inclus 2 397 971 naissances vivantes et 9 983 mortinaissances du Québec de 1981 à 2009. Pour chaque décennie, nous avons obtenu un indice d’inégalité relatif (« relative index of inequality», RII) et un indice d’inégalité absolu (« slope index of inequality», SII) pour l’association entre la scolarité maternelle et les mortinaissances, toutes causes et par cause, en ajustant pour les caractéristiques maternelles.

RÉSULTATS: Les taux de mortinaissance ont diminué pour tous les niveaux de scolarité. L’inégalité absolue de scolarité est demeurée stable (SII 2,5 pour 1 000 naissances, intervalle de confiance à 95 % 2,1–2,8; périodes combinées), tandis que l’inégalité relative a augmenté (RII 1,8 à 2,3). L’inégalité absolue a diminué pour les mortinaissances causées par un décollement placentaire (SII 0,6 à 0,3), mais a augmenté pour les causes non-spécifiées (SII 0,2 à 0,7).

CONCLUSIONS: L’inégalité absolue de scolarité pour les mortinaissances a persisté et l’inégalité relative a augmenté au cours des trois dernières décennies, malgré une diminution des taux de mortinaissance. Malgré une diminution de l’inégalité pour les décollements placentaires, on observe une augmentation pour les causes non-spécifiées. Une meilleure compréhension des composantes contribuant à ces dernières est nécessaire pour mieux appréhender les inégalités de scolarité pour les mortinaissances.

Mots Clés

cause de décès facteurs socioéconomiques mort foetale mortinaissance scolarité tendances temporelles 

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Copyright information

© The Canadian Public Health Association 2013

Authors and Affiliations

  • Noémie Savard
    • 1
  • Nathalie Auger
    • 1
    • 2
    • 3
  • Alison L. Park
    • 2
    • 3
  • Ernest Lo
    • 2
  • Jérôme Martinez
    • 2
  1. 1.Department of Social and Preventive MedicineUniversity of MontréalMontréalCanada
  2. 2.Institut national de santé publique du QuébecMontréalCanada
  3. 3.Research Centre of the University of Montréal Hospital CentreMontréalCanada

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