title: The pattern of thyroid function of subclinical hypothyroid women with levothyroxine treatment during pregnancy.
abstract: In this study, we researched the pattern of thyroid function of subclinical hypothyroid (SCH) women with levothyroxine (LT4) throughout pregnancy and determined the optimal dosages of LT4 for such women. 56 SCH pregnant women were followed regularly prospectively. They were divided into three groups: group A (n = 29. Baseline TSH between 2.5 and 5.0 mIU/L) received 50 μg/day of LT4; group B (n = 17. Baseline TSH between 5.0 and 8.0 mIU/L) received 75 μg/day of L-T4; group C (n = 10. Baseline TSH >8.0 mIU/L) received 100 μg/day of LT4. All the patients started LT4 therapy around the 8th gestational week. Serum TSH, free T4, and free T3 were measured at 4-week intervals throughout pregnancy. Among the thyroid function indexes, serum TSH changed quickly and decreased significantly 4 weeks after LT4 therapy. The change of serum FT4 responded drastically at the 12th gestational week. We also found that serum FT3 did not change much after LT4 therapy. 50, 75, and 100 μg/day can maintain serum TSH level of 79.3, 82.4, and 90.0 % of SCH women in definitive therapeutic goal in group A, B, and C, respectively. The LT4 dose need to be adjusted one or more times in 20.7, 17.6, and 10.0 % of the SCH women in group A, B, and C, respectively. The different LT4 dose can be chosen according to the baseline TSH levels of SCH women. The constant LT4 dose can maintain serum TSH levels of 79.3-90 % patients in the ideal range. A small part of patients require adjust therapy also during the second and third trimester. Therefore, careful follow-up of SCH pregnant women should be taken, and thyroid function should be tested every month until the end of pregnancy.
authors.affiliation: Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155 Nanjing Bei Street, Heping District, Shenyang, 110001, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Yu
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Chen
authors.forename: Zhongyan
authors.initials: Z
authors.lastname: Shan
authors.forename: Weiping
authors.initials: W
authors.lastname: Teng
authors.forename: Chenyang
authors.initials: C
authors.lastname: Li
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhou
authors.forename: Bo
authors.initials: B
authors.lastname: Gao
authors.forename: Tao
authors.initials: T
authors.lastname: Shang
authors.forename: Jiaren
authors.initials: J
authors.lastname: Zhou
authors.forename: Bin
authors.initials: B
authors.lastname: Ding
authors.forename: Ying
authors.initials: Y
authors.lastname: Ma
authors.forename: Ying
authors.initials: Y
authors.lastname: Wu
authors.forename: Qun
authors.initials: Q
authors.lastname: Liu
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wang
authors.forename: Yuanbin
authors.initials: Y
authors.lastname: Li
authors.forename: Chenling
authors.initials: C
authors.lastname: Fan
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zhang
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D012720:Severity of Illness Index; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000503:physiopathology*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood / Q000627:therapeutic use
chemical_list: D013972:Thyrotropin; D013974:Thyroxine