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Canadian Journal of Public Health

, Volume 97, Issue 2, pp 132–135 | Cite as

Improvements in the Status of Folate and Cobalamin in Pregnant Newfoundland Women Are Consistent with Observed Reductions in the Incidence of Neural Tube Defects

  • James D. HouseEmail author
  • Sandra B. March
  • Sam Ratnam
  • Marilyn Crowley
  • James K. Friel
Research

Abstract

Background

Historically, the province of Newfoundland and Labrador had one of the highest rates of neural tube defects (NTDs) in North America (1976–1991: 3.2/1000 births), which could be partially explained by the sub-optimal status of folate and cobalamin in this population. In order to gain evidence of the impact of folate fortification programs, as well as prenatal education programs, a cross-sectional study was conducted to obtain data on the folate and cobalamin status of pregnant Newfoundland women in the post-folate fortification era. Additionally, the rates of NTDs were determined.

Methods

Blood samples were collected during the first prenatal clinic (at approximately 16 weeks gestation) from 365 pregnant women in Newfoundland in 2002. Samples were analyzed for serum folate, cobalamin and homocysteine. In addition, rates of neural tube defects were calculated from data collected from the Provincial Medical Genetics Program, Newfoundland. Data were compared to historical data from a similar population of pregnant women in Newfoundland.

Results

The status of both folate and cobalamin has significantly improved (p<0.0001) in the post-fortification era, concurrent with a significant reduction in the number of neural tube defects (NTDs), from 4.67 (years 1992–1996) to 1.01 (years 1998–2002) per 1000 total births.

Interpretation

These data provide evidence that both folate and cobalamin status of pregnant Newfoundland women have improved since 1997. The data for cobalamin provide evidence that strategies in addition to folate fortification programs are contributing to the improvements of poor water-soluble vitamin status in this population, thus providing a partial explanation for the dramatic reductions in NTD rates observed since 1995.

MeSH terms

Folic acid cobalamin homocysteine neural tube defects 

Résumé

Contexte

Par le passé, la province de Terre-Neuve-et-Labrador avait l’un des taux d’anomalies du tube neural (ATN) les plus élevés en Amérique du Nord (1976–1991: 3,2 p. 1 000 naissances), ce qui s’expliquait en partie par le statut sous-optimal en folates et en cobalamine dans sa population. Afin d’évaluer l’impact des programmes d’enrichissement en folates et des programmes prénatals de sensibilisation, nous avons mené une étude transversale pour recueillir des données sur le statut en folates et en cobalamine des Terre-Neuviennes enceintes après l’enrichissement des aliments en folates. Nous avons aussi calculé les taux d’ATN.

Méthode

Nous avons prélevé du sang auprès de 365 femmes enceintes à Terre-Neuve en 2002 pendant leur première visite de soins prénatals (à environ 16 semaines de gestation), puis analysé les taux de folate sérique, de cobalamine et d’homocystéine dans ces échantillons. Nous avons calculé les taux d’ATN à partir des données recueillies par le programme provincial de génétique médicale de Terre-Neuve. Ces données ont été comparées aux données historiques d’une population semblable de Terre-Neuviennes enceintes.

Résultats

Le statut en folates et en cobalamine s’était significativement amélioré (p<0,0001) après la mise en oeuvre du programme d’enrichissement; en parallèle, il y a eu une baisse significative du nombre d’ATN, lequel est passé de 4,67 (1992–1996) à 1,01 (1998–2002) pour 1 000 naissances.

Interprétation

Ces données montrent que le statut en folates et le statut en cobalamine des Terre- Neuviennes enceintes se sont tous les deux améliorés depuis 1997. Les données sur la cobalamine montrent que les stratégies complémentaires aux programmes d’enrichissement en folates contribuent à l’amélioration du piètre statut en vitamines hydrosolubles dans cette population, ce qui expliquerait en partie la forte baisse des taux d’ATN observée depuis 1995.

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Copyright information

© The Canadian Public Health Association 2006

Authors and Affiliations

  • James D. House
    • 1
    • 2
    Email author
  • Sandra B. March
    • 3
  • Sam Ratnam
    • 3
  • Marilyn Crowley
    • 4
  • James K. Friel
    • 2
  1. 1.University of ManitobaWinnipegCanada
  2. 2.Department of Human Nutritional SciencesUniversity of ManitobaWinnipegCanada
  3. 3.Provincial Public Health LaboratorySt. John’sCanada
  4. 4.Department of Community MedicineMemorial University of NewfoundlandSt. John’sCanada

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