Observation of hypothyroidism during pregnancy in pregnant women with thyroid stimulating hormone level adjust-ment of levothyroxine dose variation

ZHANG Zhihui; YAN Zhaoli; HOU Junxiu; LIU Min

doi:10.3969/j.issn.1671-6450.2015.05.008

Abstract：Objective To investigate levothyroxine ( L-T4 ) variation of standard dose treatment for hypothyroidism during each stage of pregnancy ( HT) women.Methods Thirty-eight cases of pregnancy and hypothyroidism women, accord-ing to before pregnancy whether complicated with hypothyroidism, they were divided into group A with history of early hypothy-roidism( n =16);group B with no previous history of early hypothyroidism but primary screening druing pregnancy found hy-pothyroidism ( n =22) .The changes of drug dosage adjustment and thyroid function before and after substitution treatment were observed in the 2 groups of pregnant women.Results (1) Compared with before enrollment, group A’s L-T4 was in-creased at 2 months, 3 months, 6 months and 9 months of pregnancy ( t =-3.929, t =-5.692, t =-2.935, t =-4.496, P <0.05), the group B had no significant changes ( P >0.05);at the same month of pregnancy(2 months to 9 months),group A required higher dose of L-T4 than that in group B ( t =2.300, t =4.565, t =2.962, t =6.041, t =4.627, t =2.271, t =4.965, t =6.039, t =2.936, P <0.05).(2) In early pregnancy, it is needed to increase the L-T4 doses, and hypothyroidism during pregnancy increase the percentage of L-T4 dose and related to the etiology:Hashimotoˊs thy-roiditis:after hypothyroidismm L-T4 dose of 1 months, 2 months of pregnancy were increased ( t =-2.809, t =-3.261, respectively, P <0.05);idiopathic hypothyroidism, L-T4 doses at 1 months and 2 months of pregnancy were increased signifi-cantly ( t =-3.320, t =-4.459, respectively, P <0.05).(3) The effects of standard dose of L-T4 alternative treatment were affected by baseline TSH levels, according to TSH level to adjust L-T4 dose, requirement of thyroid hormone in the mid-dle and late period were gradually stabilized.Conclusion The first trimester of pregnancy or in early pregnancy, thyroid func-tion should be determined as soon as possible, for pregnant women with hypothyroidism, in accordance with the guidelines, L-T4 doses should be reached the standard as soon as possible in early pregnancy.