Fish oil contains polyunsaturated fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) which were considered as essential fatty acids. The purpose of present study was to evaluate the effects of fish oil supplementation on maternal serum fasting blood sugar (FBS), oral glucose tolerance test (OGTT), hemoglobin (Hb), and hematocrit (Hct).
In this randomized triple-blind clinical trial, 150 pregnant women were allocated into two groups randomly. In the intervention group, women received one fish oil capsule daily (1,000 mg consisted of 120 mg DHA and 180 mg EPA), and control group received placebo from the end of twentieth week of pregnancy until delivery (140 capsules). FBS, 2-hour 75 g OGTT, Hb, and Hct were measured at 6–10 and 26–30 weeks of pregnancy. Analysis was based on intervention to treat.
At the weeks 26–30, mean FBS in the intervention and control groups were 76.92 (9.8) and 75.64 (8.2) mg/dl, respectively [adjusted mean difference (aMD) (95% CI):1.46 (−2.13 to 5.05)]. Also, there was no significant difference between two groups in 2-hour OGTT [aMD (95% CI): −4.69 (−13.75 to 4.52)]. Mean (SD) Hb was 11.8 (1.1) versus 11.8 (0.7) g/dl in the intervention and control groups, respectively [aMD (95% CI): 0.001 (−0.328 to 0.330)], mean (SD) Hct were 36.12% (2.8%) and 35.84% (2.3%), respectively [aMD (95% CI): 0.25 (−0.65 to 1.14)].
Based on the findings of present study, fish oil supplementation has no significant effect on Hb, Hct, FBS and 2-hour OGTT of pregnant women.
Funding statement: This study was financially supported by the Research Vice-chancellor of Tabriz University of Medical Sciences [Grant No. 5/77/5241].
Hereby, we appreciate the Zahravi Pharmacy Company, Health Vice-chancellor of Tabriz and its authorities, all personnel of health centers and all the women who patiently assisted us to complete this study.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
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