Management of Hyperthyroidism in Pregnancy: Implications for Maternal and Fetal Outcomes
Abstract
Background: Hyperthyroidism in pregnancy, while uncommon, poses significant risks to both maternal and fetal health. The most prevalent cause is Graves' disease, an autoimmune disorder driven by thyroid-stimulating antibodies (TRAbs) that can cross the placenta. Physiological changes of pregnancy often mask or mimic symptoms of thyrotoxicosis, complicating diagnosis and potentially delaying treatment.
Aim: This review aims to synthesize the etiology, pathophysiology, and evidence-based management of hyperthyroidism in pregnancy. It emphasizes optimizing maternal and fetal outcomes through timely diagnosis, appropriate treatment, and vigilant monitoring.
Methods: A comprehensive review of the clinical approach is presented, covering the initial evaluation using trimester-specific thyroid function tests, the role of TRAb measurement for diagnosis and fetal risk stratification, and the management principles using antithyroid drugs (ATDs). The importance of fetal surveillance through ultrasound and heart rate monitoring is also detailed.
Results: Proper management, primarily with antithyroid drugs, significantly improves outcomes. A treatment strategy of Propylthiouracil (PTU) in the first trimester, transitioning to Methimazole (MMI) thereafter, balances the risks of teratogenicity and hepatotoxicity. Uncontrolled disease is linked to miscarriage, preeclampsia, and fetal thyrotoxicosis, while overtreatment can cause fetal hypothyroidism. Fetal surveillance is critical when maternal TRAbs are elevated.
Conclusion: Successful management of hyperthyroidism in pregnancy requires a multidisciplinary approach to maintain maternal euthyroidism with the lowest effective ATD dose, while conducting ongoing fetal assessment to mitigate complications.
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Authors
Copyright (c) 2024 Majdi Raji Nafaa Al-Harbi, Amal Aqeel Al-Awfi, Abrar Abdulkareem Bashir Aljohani, Afrah Sayer H Alharbi, Waad Salman Alharbi, Nader Marshwood Alsadi, Ahmad Saud Alhejaili, Ghadeer bandar Aljohani, Seham Abdullah Alamri, Alaa Hashim saib
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