Thyroid dysfunction in pregnancy

Abstract

Changes in thyroid physiology in pregnancy due to the influences of oestrogen, human chorionic gonadotrophin (hCG) and iodine metabolism have been well studied. Newer sensitive thyroid function tests have enabled identification of subtle thyroid abnormalities, such as hCG-related causes of hyperthyroidism. Graves' disease remains the commonest cause of thyrotoxicosis during pregnancy and requires careful attention. New approaches to old problems include more adequate thyroxine replacement in hypothyroid women in pregnancy. Screening for neonatal hypothyroidism has been vindicated by studies of long term outcome. The identification of thyroid dysfunction in pregnancy allows appropriate treatment and reassurance of women whose symptoms may be nonspecific.