Autoimmune Thyroid Disease in Pregnancy: A Review

Abstract

The maternal physiological changes that occur in normal pregnancy induce complex endocrine and immune responses. During a normal pregnancy, thyroid gland volume may enlarge, and thyroid hormone production increases. Hence, the interpretation of thyroid function during gestation needs to be adjusted according to pregnancy-specific ranges. The elevated prevalence of gestation-related thyroid disorders (10%-15%) and the important repercussions for both mother and fetus reported in multiple studies throughout the world denote, in our opinion, the necessity for routine thyroid function screening both before and during pregnancy. Once thyroid dysfunction is suspected or confirmed, management of the thyroid disorder necessitates regular monitoring in order to ensure a successful outcome. The aim of treating hyperthyroidism in pregnancy with antithyroid drugs is to maintain serum thyroxine (T 4 ) in the upper normal range of the assay used with the lowest possible dose of drug, whereas in hypothyroidism, the goal is to return serum thyroid-stimulating hormone (TSH) to the range between 0.5 and 2.5 mU=L.

A study of thyroid disorders in females attending obstetrics and gynecology outpatient department of a tertiary care institute of central India

“…6 Hypothyroidism is generally associated with iodine deficiency and Nepal is an endemic area of iodine deficiency with prevalence of approximately 26.5% of iodine deficiency disorder. 7 The prevalence of hypothyroidism in various studies from around the world shows a considerable variation and its current prevalence ranges from as low as 1% to as high as 20% for subclinical and 1-2% for overt hypothyroidism. 8 Although all age groups are affected by thyroid dysfunction, a high no of subjects were observed between age group of 21-50 years age (79.15%).…”

Treatment of Graves’ Disease During Pregnancy

“…Upon euthyroid, the dose may be reduced to the lowest amount to maintain the euthyroid state with serum T 4 at the upper end of normal and continued throughout pregnancy and labor. Improvement in FT 4 is usually seen in 4 weeks; whereas improvement in TSH occurs in 6-8 weeks (Galorfre, 2009). It is important not to overtreat because it may result in maternal or fetal hypothyroidsm (Casey, 2006).…”

Subclinical hypothyroidism and related biochemical entities in pregnancy: implications and management

“…7 Physiological changes in normal pregnancy (Box 1) mandate an increase in thyroid hormone production of approximately 50% to maintain adequate serum levels. 8 Goitre formation is common, especially in iodine-deficient regions, although gland enlargement by 10-20% occurs even in areas of iodine sufficiency. 9 Thyroid hormone requirements increase in hypothyroid women relying on exogenous thyroxine.…”