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

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-T4). For a woman with hypothyroidism planning pregnancy, 50% recommended increasing the dose of L-T4 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-T4. The target of thyroid function tests that responders aimed to achieve with L-T4 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.