What is the treatment for postpartum thyroiditis?

Treatment of Postpartum Thyroiditis

Treatment of postpartum thyroiditis depends on the phase of disease and severity of thyroid dysfunction, with levothyroxine indicated for TSH >10 mIU/L and beta-blockers reserved for symptomatic hyperthyroid phases. 1

Diagnostic Confirmation Before Treatment

• Confirm diagnosis with abnormal TSH level, abnormal free T4 level, or both within one year of delivery, miscarriage, or medical abortion 1
• Check thyroid peroxidase antibodies to confirm autoimmune etiology 1
• Evaluate TSH and free T4 in women who develop goiter during pregnancy/postpartum or symptoms of thyroid dysfunction 1

Treatment Algorithm by Disease Phase

Hyperthyroid (Thyrotoxic) Phase

• Beta-blockers are the primary treatment for symptomatic hyperthyroidism 2, 3
• Antithyroid drugs (methimazole, propylthiouracil) are NOT indicated because this is destructive thyroiditis with release of preformed hormone, not increased synthesis 3
• Monitor thyroid function every 2-3 weeks to detect transition to hypothyroidism 1
• This phase typically lasts 1-3 months 4

Hypothyroid Phase

Levothyroxine replacement is mandatory when TSH >10 mIU/L 1

For TSH 4-10 mIU/L, levothyroxine should be considered if:

• Patient is symptomatic 1
• Patient desires fertility 1

Dosing and monitoring:

• Adjust levothyroxine dosage to normalize TSH 1
• Since postpartum TSH levels return to pre-pregnancy values, reduce levothyroxine to pre-pregnancy dose immediately after delivery in women with pre-existing hypothyroidism 5
• Monitor TSH 4-8 weeks postpartum 5
• This hypothyroid phase typically lasts up to 6 months 4

Critical Monitoring Strategy

• Objective thyroid function testing must guide treatment decisions rather than symptoms alone, as postpartum symptoms overlap significantly with normal postpartum fatigue and mood changes 1
• Whether treatment is needed depends on severity of abnormality and symptoms 1
• Most women return to euthyroid state by 1 year postpartum 2

Long-Term Follow-Up Requirements

Women at highest risk for permanent hypothyroidism require extended monitoring:

• Those with highest TSH levels 1
• Those with highest antithyroid peroxidase antibody levels 1
• Approximately 25% of women with postpartum thyroiditis develop permanent hypothyroidism within 10 years 2, 6
• Regular screening is essential, especially before future pregnancies 7

Key Clinical Pitfalls to Avoid

• Do not use antithyroid drugs during the hyperthyroid phase - this is destructive thyroiditis, not Graves' disease 3
• Do not rely on symptoms alone - overlap with normal postpartum period makes clinical assessment unreliable 1
• Do not discontinue monitoring after initial recovery - long-term surveillance is mandatory given high rates of eventual permanent hypothyroidism 1, 2
• Do not miss the transition phase - frequent monitoring every 2-3 weeks during hyperthyroid phase prevents missing the shift to hypothyroidism 1
• Postpartum thyroiditis recurs in a high percentage of subsequent pregnancies 6