Management of hyperthyroidism during pregnancy and lactation

Area of Science:

• Endocrinology
• Maternal-Fetal Medicine
• Pharmacology

Background:

• Untreated maternal hyperthyroidism poses risks to pregnancy outcomes.
• Fetal and neonatal thyroid dysfunction can complicate intrauterine and neonatal periods.
• Effective management is essential for maternal and infant health.

Purpose of the Study:

• To review current literature on the appropriate management of hyperthyroidism in pregnant and lactating women.
• To identify optimal therapeutic strategies and potential risks associated with antithyroid drug use.

Main Methods:

• A comprehensive literature review was conducted using MEDLINE.
• Search terms included 'hyperthyroidism and pregnancy/lactation', 'antithyroid drugs', 'radioiodine', 'fetus', and 'maternal'.

Main Results:

• Antithyroid drugs, specifically methimazole (MMI) and propylthiouracil (PTU), are primary treatments.
• PTU is recommended for the first trimester, followed by MMI, to mitigate risks like fetal atresia and maternal hepatotoxicity.
• Successful therapy involves maintaining free thyroxine within the upper reference range for each trimester.
• MMI is the preferred treatment for postpartum hyperthyroidism, especially during lactation.

Conclusions:

• Hyperthyroidism management during pregnancy and lactation demands careful consideration of maternal, fetal, and neonatal well-being.
• Tailored therapeutic approaches are necessary to prevent adverse effects.
• Close monitoring and appropriate drug selection are key to successful outcomes.