Selenium supplementation in the management of thyroid autoimmunity during pregnancy: results of the 'SERENA study', a randomized, double-blind, placebo-controlled trial

Selenium is frequently in nutraceuticals for pregnancy, given its role on fertility and thyroid metabolism. However, most evidence rise from non-controlled studies. We aimed to evaluate the protective effect of selenium against thyroid autoimmunity during and after pregnancy. A multicenter, randomized, double-blind, placebo-controlled trial was performed and promoted by the Young Italian Endocrinologists Group (EnGioI)—Italian Society of Endocrinology. Forty-five women with thyroiditis in pregnancy were enrolled and randomly assigned to L-selenomethionine (L-Se-Met) 83 mcg/day or placebo (PLB) and evaluated at 10 ± 2 (T1), 36 ± 2 weeks of gestation (T2) and 6 months after delivery (postpartum, PP). We measured a significant reduction of autoantibodies after pregnancy in L-Se-Met group [at PP: TgAb 19.86 (11.59–52.60), p