Hallengren Bengt, Lantz Mikael, Andreasson Bengt, Grennert Lars
Department of Endocrinology, Malmö University Hospital, Malmö, Sweden.
Thyroid. 2009 Apr;19(4):391-4. doi: 10.1089/thy.2008.0206.
Thyroid hormones are important for normal fetal development. Maternal hypothyroidism during early pregnancy is associated with impaired neuropsychological development of children and other adverse outcomes. The primary aim of this prospective study was to determine whether thyroxine-treated pregnant women with hypothyroidism are adequately thyroxine substituted in early pregnancy. A secondary aim was to determine if fetal loss differed between females with thyrotropin (TSH) values within and outside the reference range at their first TSH test, scheduled for 1-2 weeks after verification of pregnancy.
This was a prospective open-labeled study. During the years 1997-2002, 119 consecutive pregnancies in 101 females with thyroid diseases were followed at the Department of Endocrinology, Malmö University Hospital. At the first visit, 63 patients, median age 30 years (range 17-45 years), were on thyroxine substitution therapy for hypothyroidism. In these patients 83% were in their first trimester at the time of the initial test.
Of the 63 patients on thyroxine substitution for hypothyroidism 32 (51%; Group A) patients had serum TSH values within the reference range at their initial test and 31 (49%; Group B) had serum TSH values outside the reference range. Twelve (19%) had TSH values of <0.40 mIU=L and 19 (30%) had TSH values of >4.0 mIU=l. The fetal loss was 2 of 32 (6%) in Group A compared to 9 of 31 (29%) in Group B ( p < 0.05).
In 49% of pregnant women on thyroxine substitution, serum TSH values were outside the reference range when first tested, generally in the first trimester. Fetal loss was significantly greater in pregnant women with abnormal TSH values compared to those with normal TSH values. Thyroid function in pregnant women on thyroxine substitution should be monitored early in pregnancy and carefully followed during pregnancy. The thyroxine dose should be increased as needed early in pregnancy to avoid hypothyroidism.
甲状腺激素对胎儿正常发育至关重要。孕早期母体甲状腺功能减退与儿童神经心理发育受损及其他不良后果相关。这项前瞻性研究的主要目的是确定接受甲状腺素治疗的甲状腺功能减退孕妇在孕早期甲状腺素替代是否充分。次要目的是确定在妊娠确认后1 - 2周进行首次促甲状腺激素（TSH）检测时，TSH值在参考范围内和范围外的女性胎儿丢失情况是否存在差异。
这是一项前瞻性开放标签研究。1997年至2002年期间，马尔默大学医院内分泌科对101名患有甲状腺疾病的女性的119次连续妊娠进行了随访。首次就诊时，63名患者（中位年龄30岁，范围17 - 45岁）正在接受甲状腺功能减退的甲状腺素替代治疗。在这些患者中，83%在初次检测时处于孕早期。
在63名接受甲状腺功能减退甲状腺素替代治疗的患者中，32名（51%；A组）患者初次检测时血清TSH值在参考范围内，31名（49%；B组）患者血清TSH值超出参考范围。12名（19%）患者TSH值<0.40 mIU/L，19名（30%）患者TSH值>4.0 mIU/L。A组32例中有2例（6%）发生胎儿丢失，而B组31例中有9例（29%）发生胎儿丢失（p<0.05）。
在接受甲状腺素替代治疗的孕妇中，49%在首次检测时（通常在孕早期）血清TSH值超出参考范围。与TSH值正常的孕妇相比，TSH值异常的孕妇胎儿丢失明显更多。接受甲状腺素替代治疗的孕妇的甲状腺功能应在孕早期进行监测，并在孕期密切随访。应在孕早期根据需要增加甲状腺素剂量以避免甲状腺功能减退。
