title: Folic Acid Supplementation in Pregnancy and the Risk of Pre-Eclampsia-A Cohort Study.
abstract: This prospective cohort study designed to assess the effect of folic acid supplementation in pregnancy on the risk of preeclampsia (PE) took place in Ottawa, ON and Kingston, ON, Canada, from September 1, 2002 to August 31, 2008. Pregnant women, less than 20 weeks gestational age were recruited and delivered in the Ottawa region and the Kingston General Hospital. Demographic characteristics of the study participants and the patterns of supplementation of folic acid were described and occurrence of PE between women with folic acid supplementation during pregnancy and women without were compared. Multiple logistic regression was used in the estimation of the independent effect of supplementation of folic acid. Additional analyses assessing the effect of low RBC and serum folate and dose-response relationship were performed. Analyses were performed in all study participants, and then in high risk and low risk sub-groups, respectively. A total of 7,669 participants were included in the final analysis. Ninety five percent of the study participants were taking folic acid supplementation in early second trimester. The rate of PE was lower in the supplementation group than in the no supplementation group, and the difference was statistically significant in high risk women. Similar patterns of associations were observed in analysis by RBC and serum folate levels and in dose-response analysis. Folic acid supplementation in pregnancy may reduce PE risk in pregnant women, especially in those women with increased risk of developing PE.
authors.affiliation: OMNI Research Group, Department of Obstetrics and Gynecology, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.|Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.|School of Epidemiology, Public Health, and Preventive Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.
authors.forename: Shi Wu
authors.initials: SW
authors.lastname: Wen
authors.affiliation: OMNI Research Group, Department of Obstetrics and Gynecology, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.|Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.|School of Epidemiology, Public Health, and Preventive Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.|Division of Hematology, Department of Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Rodger
authors.affiliation: OMNI Research Group, Department of Obstetrics and Gynecology, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.|Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.
authors.forename: Ruth Rennicks
authors.initials: RR
authors.lastname: White
authors.affiliation: Public Health Agency of Canada, Ottawa, Ontario, Canada.
authors.forename: Qiuying
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Queen's Perinatal Research Unit, Kingston General Hospital, Kingston, Ontario, Canada.|Department of Obstetrics and Gynecology, Queen's University School of Medicine, Kingston, Ontario, Canada.
authors.forename: Graeme N
authors.initials: GN
authors.lastname: Smith
authors.affiliation: Division of Biochemistry, The Ottawa Hospital, Ottawa, ON, Canada.
authors.forename: Sherry L
authors.initials: SL
authors.lastname: Perkins
authors.affiliation: OMNI Research Group, Department of Obstetrics and Gynecology, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.|Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada.|School of Epidemiology, Public Health, and Preventive Medicine, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Walker
mesh_terms: D000328:Adult; D002170:Canada; D015331:Cohort Studies; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005865:Gestational Age; D006801:Humans; D016015:Logistic Models; D011225:Pre-Eclampsia / Q000097:blood / Q000517:prevention & control*; D011247:Pregnancy; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D005492:Folic Acid