Treatment and screening of hypothyroidism in pregnancy: results of a European survey

Abstract

Background: Maternal hypothyroidism in pregnancy is associated with several adverse outcomes. The Endocrine Society Guidelines for the management of thyroid diseases in pregnancy were published in 2007; however, impact of the guidelines in routine clinical practice is unknown. Therefore, we have carried out a survey of members of the European Thyroid Association (ETA) to study current practices relating to the management of hypothyroidism in pregnancy. Subjects and methods: In December 2010, we emailed an electronic questionnaire survey based on clinical case scenarios to 605 members of the ETA. Responses from 190 clinician members (from 28 European countries) were analyzed. Results: For a pregnant woman with newly diagnosed overt hypothyroidism, most responders initiated a full dose of L-thyroxine (L-T 4 ). For a woman with hypothyroidism planning pregnancy, 50% recommended increasing the dose of L-T 4 as soon as pregnancy is confirmed, whilst 43% favored testing thyroid function before adjusting the dose. Responders used diverse combinations of tests to monitor the dose of L-T 4 . The target of thyroid function tests that responders aimed to achieve with L-T 4 was also inconsistent. Forty-two percent responders or their institutions screened all pregnant women for thyroid dysfunction, 43% performed targeted screening of only the high-risk group, whilst 17% did not carry out systemic screening. Timing of the screening, tests used, and criteria for starting treatment and monitoring were variable. Conclusions: There is wide variation in the clinical practice relating to the treatment and screening of hypothyroidism during pregnancy in Europe.

CONTROVERSIES IN ENDOCRINOLOGY: On the need for universal thyroid screening in pregnant women

“…However, focusing exclusively on high-risk pregnancies could leave between one-and two-thirds of women with SChypo undiagnosed (21). A recent questionnaire concerning the clinical practice of screening for thyroid disease in pregnancy included 605 members of the European Thyroid Association (22). Forty-two percent of responders screen all women for TD, 43% perform targeted screening of the high-risk group, whilst 17% do not perform screening.…”

An international survey of screening and management of hypothyroidism during pregnancy in Latin America

“…In 2010, significant variability in diagnostic and therapeutic management have been reported by a questionnaire which assessed management of hypothyroidism during pregnancy in Europe (6). However, even with novel prospective studies, many controversies still exist regarding the most appropriate approach for the L-T 4 dose adjustment in pregnancy (7,8).…”

Screening of High-Risk Pregnant Women for Thyroid Dysfunctions in a Moderately Mild Iodine-Deficient Area

“…It was suggested, that the cause of isolated hypothyroxinemia is iodine deficiency instead of autoimmune thyroid processes, such as among 56/220 (25.4%) pregnant women with isolated hypothyroxinemia TPO-Ab were detectable in only 7.1% of them (Moleti et al, 2009). Data published so far are not sufficient to recommend thyroxine replacement therapy in this case in pregnancy, although a study analysing questionnaires about the treatment of hypothyroidism during pregnancy filled in by over 600 members of the European Thyroid Society (ETA) showed that 38% of the responders would treat isolated maternal hypothyroxinemia, but the responders' definition of this disorder was not consistent (Vaidya et al, 2012), which reflects the lack of clear definition and management of this state.…”

“…This definition is not well delineated in the literature, because the reference range of TSH-level varies between large limits according to different authors and the gestational trimester (Vaidya et al, 2012;Glinoer & Abalovich, 2007;Burman, 2009). We have evaluated the TSH-and FT4-values based on the above mentioned normal intervals.…”

“…Other authors recommended for women who became pregnant to increase the dose of levothyroxine by 30-50%. Several authors would first check thyroid function tests before adjusting the dose (Vaidya et al, 2012). Thyroid hormone levels must be monitored at least every 4 week until 20 th weeks, because the required doses of T4 increase during pregnancy.…”