Folic acid supplementation and dietary folate intake, and risk of preeclampsia

Abstract

BACKGROUND/OBJECTIVES Folic acid supplementation has been suggested to reduce the risk of preeclampsia. However, results from few epidemiologic studies have been inconclusive. We investigated the hypothesis that folic acid supplementation and dietary folate intake before conception and during pregnancy reduce the risk of preeclampsia. SUBJECTS/METHODS A birth cohort study was conducted in 2010–2012 at the Gansu Provincial Maternity & Child Care Hospital in Lanzhou, China. A total of 10 041 pregnant women without chronic hypertension or gestational hypertension were enrolled. RESULTS Compared with nonusers, folic acid supplement users had a reduced risk of preeclampsia (OR = 0.61, 95% CI: 0.43–0.87). A significant dose–response of duration of use was observed among women who used folic acid supplemention during pregnancy only (P-trend = 0.007). The reduced risk associated with folic acid supplement was similar for mild or severe preeclampsia and for early- or late-onset preeclampsia, although the statistical significant associations were only observed for mild (OR = 0.50, 95% CI: 0.30–0.81) and late-onset (OR = 0.60, 95% CI: 0.42–0.86) preeclampsia. The reduced risk associated with dietary folate intake during pregnancy was only seen for severe preeclampsia (OR = 0.52, 95% CI: 0.31–0.87, for the highest quartile of dietary folate intake compared with the lowest). CONCLUSIONS Our study results suggest that folic acid supplementation and higher dietary folate intake during pregnancy reduce the risk of preeclampsia. Future studies are needed to confirm the associations.

Folic acid supplementation, dietary folate intake and risk of preterm birth in China

“…The study population has been described previously [35][36][37]. In brief, a birth cohort study was conducted during 2010-2012 at the Gansu Provincial Maternity & Child Care Hospital, the largest maternity and child care hospital in Lanzhou, China.…”

“…Data collection on folic acid supplementation and dietary folate intake has been described previously [37]. Briefly, information on folic acid supplements was asked for the following four time periods: preconception (12 months before pregnancy), first trimester (1-13 weeks), second trimester (14-27 weeks), and third trimester (>27 weeks).…”

“…Dietary information was collected via a semi-quantitative food frequency questionnaire. Daily dietary folate intake was estimated from the frequency of consumption and portion size of food items using the Chinese Standard Tables of Food Consumption [40], for each time period [37].…”

Maternal folic acid supplementation for the prevention of preeclampsia: A systematic review and meta‐analysis

“…No non‐English language studies were found for full text review. Ten studies were assessed as meeting the a priori inclusion criteria and were included in this systematic review …”

Comparison of high dose and low dose folic acid supplementation on prevalence, onset and severity of preeclampsia

“…[35] A recent chines study revealed that folic acid supplementation can significantly decrease risk of PE, but in contrast to our data they found an association between intake of folic acid supplementation and mild late-onset presentation of the disorder. [36] A study designed by Bodnar et al . showed a 45% decreased risk of PE during pregnant women who intake multivitamin compared with those nonusers.…”