title: Absence of association between serum folate and preeclampsia in women exposed to food fortification.
abstract: OBJECTIVE
  To evaluate serum folate concentration early in pregnancy and any association with hypertensive disorders of pregnancy in a population exposed to folic acid supplementation and food fortification.
  
  
  METHODS
  This is a nested case-control study based on a prospective cohort of 7,929 pregnant women recruited in the Quebec City metropolitan area, including 214 participants who developed a hypertensive disorder of pregnancy and 428 normotensive participants in the control group matched for parity, multiple pregnancy, smoking status, gestational, and maternal age at inclusion, and duration of blood sample storage. Serum folate levels were measured at a mean of 14 weeks of gestation.
  
  
  RESULTS
  More than 98% of the participants took folic acid or multivitamins before the end of the first trimester. Mean serum folate levels were accordingly high and there were no differences between women who further developed a hypertensive disorder of pregnancy compared with women in the control group (60.1 nmol/L compared with 57.9 nmol/L; P=.51). The proportion of participants with serum folate below the 10th percentile (less than 22.3 nmol/L) of age-matched women in our outpatient population was similar between groups (P=.66) and no participant had levels generally defined as folate deficiency (less than 10 nmol/L).
  
  
  CONCLUSIONS
  In a general cohort of pregnant women benefiting from a national policy of folic acid food fortification combined with a high adherence to folic acid supplementation, serum folate levels are high and do not differ between women who develop a hypertensive disorder of pregnancy and women who remain normotensive. Further supplementation with higher doses is unlikely to be beneficial in such populations.
  
  
  METHODS
  II.
authors: CHU de Québec Research Center, Hôpital St-François d'Assise, CHU de Québec, Hôpital de l'Enfant Jésus, and CHU de Québec, Centre hospitalier de l'Université Laval (CHUL), Quebec City, and CHU Sainte-Justine, Montréal, Québec, Canada.
authors: Sébastien
authors: S
authors: Thériault
authors: Yves
authors: Y
authors: Giguère
authors: Jacques
authors: J
authors: Massé
authors: Sébastien B
authors: SB
authors: Lavoie
authors: Joël
authors: J
authors: Girouard
authors: Emmanuel
authors: E
authors: Bujold
authors: Jean-Claude
authors: JC
authors: Forest
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000097:blood*; D011247:Pregnancy; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D005492:Folic Acid
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