Thyroid Research and Practice

: 2008  |  Volume : 5  |  Issue : 1  |  Page : 6--10

Thyroid disease and pregnancy

A Mazumdar, D Maji 
 Endocrine unit, Vivekananda Institute of Medical Sciences, Kolkata

Correspondence Address:
A Mazumdar
Endocrine unit, Vivekananda Institute of Medical Sciences, Kolkata

Thyroid disease is common in younger women and may be a factor in reproductive dysfunction. Once adequately treated this disorder is associated with successful pregnancy outcome. The key is to recognize and to treat thyroid disorders in the reproductive-age woman before conception. Pregnancy is a euthyroid state that is normally maintained by complex changes in thyroid physiology. The fetal hypothalamic-pituitary-thyroid system develops independently and the process is generally complete by the 12 th week of intrauterine life. Early pregnancy is characterized by an increase in maternal T4 secretion stimulated by hCG and an increase in TBG, resulting in elevated total serum T4 in pregnancy. Maternal T4 is important in fetal brain development. There is evidence in human subjects that substantial maternal T4 can cross the placenta during pregnancy, and this is particularly important when there is fetal thyroid agenesis. Maternal and fetal/ neonatal outcomes in pregnancy are adversely affected if severe hypothyroidism is undiagnosed or inadequately treated. Thyroid function tests should be obtained during gestation in women taking thyroxine and appropriate dose adjustments should be made for Free T4 and TSH levels outside the normal range. TSH-receptor blocking antibodies from the mother are a recognized cause of congenital hypothyroidism in the fetus and neonate that can be permanent or transient. Pathophysiologic conditions of hCG secretion such as gestational trophoblastic disease and hyperemesis gravidarum may present as thyrotoxicosis in the first trimester of pregnancy. However the main cause of hyperthyroidism in pregnancy is Graves «SQ» disease. The mainstay of treatment is antithyroid drugs and either propylthiouracil or methimazole may be used safely. Subtotal thyroidectomy, after medical control, is the alternative treatment, but radioiodine ablation is contraindicated. Postpartum thyroiditis can present with transient hyperthyroidism which subsequently evolves into hypothyroidism.

How to cite this article:
Mazumdar A, Maji D. Thyroid disease and pregnancy.Thyroid Res Pract 2008;5:6-10

How to cite this URL:
Mazumdar A, Maji D. Thyroid disease and pregnancy. Thyroid Res Pract [serial online] 2008 [cited 2020 Sep 20 ];5:6-10
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