Physiologic changes during pregnancy have a profound impact on the thyroid gland and thyroid function. Subclinical hypothyroidism (SCH) is a common pregnancy-related thyroid disorder. The ATA/AACE Guidelines recommend to maintain the thyroid hormones levels within the normal range during pregnancy, to avoid the risk of arising mother and fetal complications. This paper draws attention to the importance of prevention of these events during the gestation period. Here the author describes a recent case report of a 31-year-old pregnant woman with borderline thyroid hormones levels, who was administered with myo-inositol plus selenium throughout all pregnancy to prevent SCH and associated adverse maternal/neonatal outcomes. A trimester-specific screening revealed that serum TSH, fT4 and fT3 remained stable during 9 months of pregnancy. Our experience may open a new scenario in the prevention of SCH in pregnant women at risk of developing this disorder.