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

Document Type : Original Article


1 Department of Obstetrics and Gynecology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, I.R., Iran

2 Department of Community Health, Social Health Determinants Research Center, Shahrekord University of Medical Sciences, Shahrekord, I.R., Iran


Background: Folic acid supplementation had previously mentioned as a protective factor against the onset of preeclampsia (PE). In this study, we aimed to compare the effect of high dose (5 mg daily) and low dose (1 mg daily) of folic acid supplementation on prevalence, onset and severity of PE.
Materials and Methods: Pregnant women who were in the first trimester and referred to prenatal care university hospitals of Isfahan, Iran during October 2013–May 2015 were included in this study, then they were randomly divided into two groups of 5 mg and 1 mg (treated with daily 5 mg and 1 mg of folic acid, respectively), both groups received folic acid from the first trimester of pregnancy to 42 days after termination. Blood pressure, body mass index (BMI), and some urine and blood biochemistry parameters were measured. SPSS-22 used for statistical analysis.
Results: A total of 943 pregnant women participated in the study (450 women in 1 mg group and 450 women in 5 mg group). Incidence rate of PE was 3.8% in 1 mg group and 2.4% in 5 mg group. In a comparison of preeclamptic patients in 1 mg and 5 mg group, no significant differences were seen regarding age, BMI, laboratory data, the severity of the disease, and onset (early or late) (P > 0.05).
Conclusion: Although our findings support that administration of high dose folic acid may decrease the prevalence of PE, there is not enough data to support that higher amount of folic acid administration can reduce the severity of presentation's signs or ameliorate the laboratory data and the onset of PE.


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