Effect of L -thyroxine supplementation on very low birth weight infants with transient hypothyroxinemia of prematurity at 3 years of age

Objective:to evaluate the effects of levothyroxine (l-t4) supplementation on growth and neurodevelopmental outcomes at 3 years of age in very low birth weight (vlbw) infants with transient hypothyroxinemia of prematurity (thop).study design:vlbw infants with plasma thyroid-stimulating hormone concentrations <10 miu l−1 and free thyroxine concentrations <0.8 ng dl−1 were defined as having thop and randomly assigned to the treated (20 infants) or untreated (31 infants) group. the treated group received l-t4 at a dose of 5 μg kg−1 day−1. growth and neurodevelopmental outcomes at 3 years of age were compared between the two groups.results:there were no significant differences in body length, body weight or head circumference mean s.d. scores or in neurodevelopmental outcomes between the two groups.conclusion:l-t4 supplementation in vlbw infants with thop demonstrated no beneficial effect at 3 years of age.