Objective:To investigate the effect of ultrasound monitoring of thyroid measured values on evaluating the prognosis of infants with congenital hypothyroidism. Methods:A total of 74 infants with congenital hypothyroidism who were screened out by Mianyang Branch of Sichuan Provincial Center of Screening for Neonatal Inherited Metabolic Diseases from August 2015 to August 2016 were enrolled as study group

and 74 healthy infants were enrolled as control group. A retrospective analysis was performed for related data

including left-right diameter

anteroposterior diameter

and superior-inferior diameter of the thyroid and the size of the isthmus of thyroid gland（anteroposterior diameter） at the age of 1

6

12

24

and 36 months. Results:Compared with the control group

the study group had a significantly lower anteroposterior diameter of the thyroid at different ages in months（P < 0.05）. There were no significant differences between the two groups in the left-right diameter and the superior-inferior diameter of the thyroid and the anteroposterior diameter of the isthmus of thyroid gland at different ages in months（P > 0.05）.In the patients of study group

who were continuously treated until the age of 3 years

the increase in the size of the thyroid was positively correlated with normal results of the serum thyroid function test（TSH

T3

and T4）（r = 0.99

P < 0.05）

and the decrease in the size of the thyroid was negatively correlated with normal results of the serum thyroid function test（TSH

T3

and T4）（r =-0.912

P < 0.05）. Conclusion:Dynamic ultrasound monitoring of thyroid measured values

especially the anteroposterior diameter of thyroid

has a certain effect in evaluating the prognosis of congenital hypothyroidism.