The Effect of Selenium Supplementation on Clinical Outcomes, Metabolic Profiles, and Pulsatility Index of the Uterine Artery in High-Risk Mothers in Terms of Preeclampsia Screening with Quadruple Test: a Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Randomized, double-blind, placebo-controlled clinical trial in high-risk pregnant women screened for preeclampsia with quad marker testing. In the selenium arm, 30 participants were randomized and 24 were analyzed/completed; enrollment occurred at Shahid Beheshti Hospital in Kashan, Iran, from May 2020 to December 2020.

The active regimen was selenium 200 µg/day as selenium amino acid chelate, taken with meals for 12 weeks starting at 16 to 18 weeks of gestation. This was compared with placebo in a randomized, double-blind trial.

Selenium supplementation produced a favorable overall effect in this high-risk pregnancy population. Compared with placebo, it increased serum selenium levels (β 22.25 mg/dL; 95% CI, 18.3 to 26.1; P < 0.001), TAC (β 82.88 mmol/L; 95% CI, 3.03 to 162.73; P = 0.04), and GSH (β 71.35 µmol/L; 95% CI, 5.76 to 136.94; P = 0.03), while reducing hs-CRP (β -1.52; 95% CI, -2.91 to -0.14; P = 0.03) and uterine artery pulsatility index (β -0.09; 95% CI, -0.14 to -0.04; P = 0.04). Depression, anxiety, and sleep quality also improved (all P < 0.001), with no reported adverse events and no significant changes in other metabolic profiles.

The selenium arm had a small analyzed sample size (24 participants) and the intervention lasted only 12 weeks, limiting certainty about longer-term maternal and fetal outcomes. The trial was single-center and included a selected high-risk pregnancy population, which may reduce generalizability.