Abstract
OBJECTIVES: To evaluate the efficacy of levothyroxine (L-T4) suppression therapy in women with a history of differentiated thyroid carcinoma (DTC), focusing on pregnancy outcome after thyroidectomy. METHODS: This retrospective study included 300 pregnancies in women with previous DTC surgery. Participants were divided into an experimental group (n=187) receiving L-T4 doses adjusted based on thyroid-stimulating hormone (TSH) levels and a control group (n=113) following a fixed low-dose L-T4 regimen. We assessed various outcomes, including biochemical values (TSH dynamics, lipid profile, folic acid [FA] levels), obstetric measures (placental function, pregnancy complications), and neonatal outcomes. RESULTS: The experimental group showed consistently lower TSH levels throughout pregnancy and experienced fewer pregnancy and neonatal complications compared to the control group (all P<0.05). Additionally, the experimental group demonstrated significant improvements in lipid profiles, FA levels, and placental function(all P<0.05). CONCLUSIONS: TSH-adjusted L-T4 therapy in pregnant women post-DTC thyroidectomy results in better maternal and neonatal outcomes compared to a fixed low-dose L-T4 regimen. This approach optimizes TSH stability, improves lipid and FA profiles, and enhances placental function, leading to improved overall outcomes for both the mother and child.