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Published on: July 13, 2014
Second trimester folate status and preterm birth
Anna Maria Siega-Riz1, David A Savitz, Steven H Zeisel
1Carolina Population Center, CB # 8120 University Square, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516-3997, USA. am_siegariz@unc.edu
Objective:
The purpose of this study was to show that maternal folate status during pregnancy may be related to preterm birth.
Study Design:
Women were recruited at 24 to 29 weeks' gestation from 1995 to 2000 into the Pregnancy, Infection, and Nutrition Study. Those who completed an interview and a food frequency questionnaire, or provided a blood sample for radioassay of serum (n = 2026) and red blood cell (n = 1034) folate were included.
Results:
Mean daily dietary folate intake was 463 microg (SD +/- 248). Intake =500 microg was associated with increased preterm delivery (RR = 1.8, 95% CI 1.4-2.6) controlling for total energy intake. Serum folate levels <16.3 ng/mL and red blood cell folate levels =626.6 ng/mL yielded adjusted risk ratios of 1.8 (95% CI 1.3-2.5) and 1.7 (95% CI 1.1-2.6), respectively. Patterns were similar for spontaneous and overall preterm birth.
Conclusion:
These results support the hypothesis that low folate levels during the second trimester of pregnancy are associated with an increased risk of preterm birth.
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