Levothyroxine treatment for subclinical hypothyroidism during pregnancy and the subsequent neuropsychological development of the offspring: a prospective epidemiological study / 中华内分泌代谢杂志

ABSTRACT

Objective To prospectively observe the effect of levothyroxine treatment on neuropsychological development in offspring of pregnant women with subclinical hypothyroidism. Methods Twenty-three pregnant women with subclinical hypothyroidism received levothyroxine therapy (SCH+LT4 group) and 17 who did not receive levothyroxine ( SCH group) were enrolled; 24 pregnant women with normal thyroid function were referred as controls (C group). All the subjects underwent the planned thyroid tests regularly. Serum TSH, TT4, FT4, TT3,FT3, TPOAb, and TgAb levels were determined. Their 14-30 month-old children underwent the tests relating to intelligence and motor activity with the Bayley scale. Results In SCH group, SCH+LT4 group, and C group, the MDI were 115. 12, 118.56, and 117.63, respectively. And the PDI were 115.47, 120.65, and 117.50,respectively. The MDI and PDI were the highest in SCH+LT4 group and were the lowest in SCH group. Serum TSH levels remained above 2.0 mIU/L during the whole course of pregnancy in SCH group and higher than that in C group at all time points ( P＜0.05 ). Serum TT4 and FT4 levels were lower in SCH group than in C group at all time points except G28 and G32. The baseline TSH level in SCH+LT4 group was the highest ( P＜0.01 ), their TT4 and FT4 levels were the lowest among the three groups. In SCH + LT4 group, serum TSH, TT4, and FT4 levels were similar to C group after L-T4 treatment. Conclusion The prompt L-T4 treatment can maintain normal TSH levels in pregnant women with subclinical hypothyroidism during the whole course of pregnancy, and impairment of neuropsychological development in infants may be avoided.