Practical aspects in the management of thyroid diseases in pregnancy are reviewed. Information on the hypothalamic-pituitary thyroid axis function in pregnancy and transplacental passages of thyroid hormones is discussed. Diagnosis and management of thyroid dysfunction in pregnancy are updated together with the management of women on thyroid replacement therapy at the time of conception. A practical evaluation of thyroid nodules in pregnancy is suggested. Finally, the syndrome of postpartum thyroid dysfunction is reviewed, stressing the importance of proper diagnosis and the need for long-term follow-up evaluation of these patients.