Levothyroxine for subclinical hypothyroidism during pregnancy: an updated systematic review and meta-analysis of randomized controlled trials.

Purpose: We aimed to perform a systematic review and meta-analysis addressing the efficacy of levothyroxine therapy in pregnant women with subclinical hypothyroidism considering most recent evidence and subgroups of interest for clinical practice.

Methods: PubMed, Embase, and Cochrane Central were searched from inception for randomized controlled trials (RCTs) comparing levothyroxine with placebo or no intervention in pregnant women with subclinical hypothyroidism. We used a random-effects model and conducted subgroup analyses based on thyroid peroxidase antibody status, thyroid stimulating hormone levels, fertility treatment, and recurrent miscarriage.