Hyperthyroidism during pregnancy: Treatment
- Douglas S Ross, MD
Douglas S Ross, MD
- Section Editor — Thyroid Disease
- Professor of Medicine
- Harvard Medical School
- Section Editors
- David S Cooper, MD
David S Cooper, MD
- Editor-in-Chief — Endocrinology
- Section Editor — Pituitary Disease; Thyroid Disease
- Professor of Medicine and International Health
- Johns Hopkins University School of Medicine
- Charles J Lockwood, MD, MHCM
Charles J Lockwood, MD, MHCM
- Section Editor — Obstetrics
- Senior Vice President, USF Health
- Dean, Morsani College of Medicine
- Professor, Obstetrics and Gynecology
- University of South Florida
The treatment of pregnant women with hyperthyroidism parallels that of nonpregnant women but presents unique problems. There are several important issues to be considered when hyperthyroidism occurs during pregnancy. These include understanding indications for treatment, therapeutic options for pregnant women, and goals of antithyroid drug (ATD) therapy.
The treatment of hyperthyroidism during pregnancy is presented here. The clinical manifestations, diagnosis, and causes of hyperthyroidism and other aspects of thyroid disease during pregnancy are discussed separately. (See "Hyperthyroidism during pregnancy: Clinical manifestations, diagnosis, and causes" and "Overview of thyroid disease in pregnancy".)
OVERVIEW OF TREATMENT
The Endocrine Society and the American Thyroid Association (ATA) have published clinical guidelines for the management of thyroid dysfunction during pregnancy that are similar to the approach outlined here [1-3]. Treatment recommendations are predominantly based upon observational studies and clinical experience.
Goals — A good fetal and maternal outcome depends upon controlling the mother's hyperthyroidism. There are changes in thyroid physiology during normal pregnancy that are reflected in altered thyroid function tests. Thyroid function tests, therefore, should be interpreted with an understanding of trimester-specific reference ranges for the individual tests. (See "Overview of thyroid disease in pregnancy", section on 'Trimester-specific reference ranges'.)
The goal of treatment is to maintain persistent but mild hyperthyroidism in the mother in an attempt to prevent fetal hypothyroidism . Overtreatment of maternal hyperthyroidism with thionamide antithyroid drugs (ATDs) can cause fetal goiter and primary hypothyroidism. On the other hand, transient central hypothyroidism may be seen in infants whose mothers had poorly controlled hyperthyroidism during pregnancy, presumably due to suppression of the fetal pituitary-thyroid axis .
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- OVERVIEW OF TREATMENT
- Indications for treatment
- Therapeutic options
- OUR APPROACH
- Control of symptoms
- Decrease thyroid hormone synthesis
- - Pretreatment evaluation
- - Choice of thionamide
- - Initial dosing
- - Monitoring and dose adjustments
- - Thionamide intolerance
- Is there a role for iodine as primary therapy for hyperthyroidism?
- Therapies not recommended
- History of treated hyperthyroidism
- FETAL OR NEONATAL HYPERTHYROIDISM
- Measurement of maternal antibodies
- Fetal monitoring
- - Ultrasound
- - Fetal blood sampling
- POSTPARTUM ISSUES
- SOCIETY GUIDELINE LINKS
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS