Aug 12, 2013 - Methods: The Norwegian Mother and Child Cohort Study is a ...... the Swedish Medical Society (SLS 2008â21198) and Swedish government.
Sengpiel et al. BMC Pregnancy and Childbirth 2013, 13:160 http://www.biomedcentral.com/1471-2393/13/160
RESEARCH ARTICLE
Open Access
Folic acid supplementation, dietary folate intake during pregnancy and risk for spontaneous preterm delivery: a prospective observational cohort study Verena Sengpiel1*, Jonas Bacelis1, Ronny Myhre2, Solveig Myking2, Aase Devold Pay3, Margaretha Haugen4, Anne-Lise Brantsæter4, Helle Margrete Meltzer4, Roy M Nilsen5, Per Magnus6, Stein Emil Vollset7, Staffan Nilsson8 and Bo Jacobsson1,2
Abstract Background: Health authorities in numerous countries recommend periconceptional folic acid to pregnant women to prevent neural tube defects. The objective of this study was to examine the association of folic acid supplementation during different periods of pregnancy and of dietary folate intake with the risk of spontaneous preterm delivery (PTD). Methods: The Norwegian Mother and Child Cohort Study is a population-based prospective cohort study. A total of 65,668 women with singleton pregnancies resulting in live births in 1999–2009 were included. Folic acid supplementation was self-reported from 26 weeks before pregnancy until week 24 during pregnancy. At gestational week 22, the women completed a food frequency questionnaire, which allowed the calculation of their average total folate intake from foods and supplements for the first 4–5 months of pregnancy. Spontaneous PTD was defined as the spontaneous onset of delivery between weeks 22+0 and 36+6 (n = 1,628). Results: The median total folate intake was 266 μg/d (interquartile range IQR 154–543) in the overall population and 540 μg/d (IQR 369–651) in the supplement users. Eighty-three percent reported any folic acid supplementation from
