Folic acid supplementation in early second trimester and the risk of preeclampsia.
OBJECTIVE
The objective of the study was to evaluate the association between folic acid supplementation in early second trimester and the risk of developing preeclampsia.


METHODS
We carried out a prospective cohort study between October 2002-December 2005. We recruited women who had their prenatal care visit (12-20 weeks' gestation) at the Ottawa Hospital and Kingston General Hospital. All charts for participants with a diagnosis of preeclampsia were audited and blindly adjudicated by 4 study investigators to validate the diagnosis.


RESULTS
A total of 2951 pregnant women were included in the final analysis. Supplementation of multivitamins containing folic acid was associated with increased serum folate (on average 10.51 micromol/L), decreased plasma homocysteine (on average 0.39 micromol/L), and reduced risk of preeclampsia (adjusted odds ratio, 0.37; 95% confidence interval, 0.18-0.75).


CONCLUSIONS
Supplementation of multivitamins containing folic acid in the second trimester is associated with reduced risk of preeclampsia.
Wen
Shi Wu
SW
OMNI Research Group, Department of Obstetrics and Gynecology, University of Ottawa, Faculty of Medicine, Ottawa, Ontario, Canada. swwen@ohri.ca
Chen
Xi-Kuan
XK
Rodger
Marc
M
White
Ruth Rennicks
RR
Yang
Qiuying
Q
Smith
Graeme N
GN
Sigal
Ronald J
RJ
Perkins
Sherry L
SL
Walker
Mark C
MC
D000328:Adult; D015331:Cohort Studies; D016001:Confidence Intervals; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D016017:Odds Ratio; D011225:Pre-Eclampsia / Q000453:epidemiology* / Q000517:prevention & control; D011247:Pregnancy; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D011295:Prenatal Care / Q000379:methods; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values; D018570:Risk Assessment
D005492:Folic Acid