Postpartum thyroiditis E05.9

Hyperthyroidism after pregnancy is either caused by postpartum thyroiditis or by a recurrence of immune hyperthyroidism (Graves' disease).

Postpartum thyroiditis is classified as a variant of accelerated chronic lymphocytic thyroiditis (Hashimoto). It is called post-partum thyroiditis if it develops within a period of 12 months after delivery.

4% of pregnant women (Abalovich M et al. 2007)

Mostly unclear. Drugs can be triggering (e.g. amiodarone, interferon-alpha, interleukin-2). There is an association with HLA-DR3

The disease causes no pain. It often occurs as silent or silent thyroiditis. Women who already have elevated thyroid antibodies (TPO antibodies) before or during pregnancy are particularly at risk. Furthermore, women with a predisposition to chronic lymphocytic thyroiditis (Hashimoto) or autoimmune thyroiditis of the Graves' type as well as diabetes patients (Nicholson WK et al. (2006).

The disease often has a triphasic course:

• Initially it can go completely unnoticed (silent hyperthyroidism). The diagnosis is then a random finding (pathological laboratory values). More severe symptoms are signs of hyperthyroidism with tremors, nervousness, tachycardia and increased sweating. The hyperthyroid phase is caused by the inflammatory release of stored thyroglobulin. It lasts a few weeks and is self-limiting.
• Phase of hypothyroidism. During this time, patients suffer from fatigue and lack of drive.
• The third phase is characterized by a normalized, euthyroid functional position.

MAK/TPO antibodies are positive in 50-70% of cases. Antibodies against thyroglobulin (TAK) are positive in 20-40% of cases. Antibodies against TSH antibodies (TSH-R antibodies) are positive in 10-30% of cases.

Postpartum thyroiditis is treated symptomatically with beta-blockers if necessary (e.g. clear clinical signs of hyperthyroidism). Hypothyroidism then usually develops until the hormone synthesis has recovered. Therapy with levothyroxine is recommended from a TSH value > 10 mU/l. However, most women show a normalization of thyroid function within 1 year. Stop the levothyroxine therapy.

In half of the women the disease spontaneously normalizes after one year.

There is a significantly increased risk of developing permanent hypothyroidism in the following years. In this respect, annual thyroid function checks are indicated

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