Postpartum thyroiditis

Postpartum thyroidits is a form of autoimmune subacute thyroiditis which affects postpartum women. It’s likely that postpastum thyroiditis is an accelerated form of Hashimoto thyroiditis which is triggered by the pregnancy, as 50% of cases were anti-TPO positive ahead of pregnancy.

It occurs in 5 – 10% of deliveries.

Clinical features

It develops within 6 months after delivery. The goitre is painless. As in other cases of thyroiditis, there is an initial phase of thyrotoxicosis followed by a later phase of hypothyroidism.

Diagnosis and evaluation

Diagnosis is based on:

• Typical clinical features
• Ultrasound findings (inhomogenous, hypoechogenic thyroid)
• Normal leukocyte count
• Extremely high ESR
• Initial thyrotoxicosis followed by hypothyroidism
• Presence of anti-thyroid antibodies (anti-TPO, anti-Tg)

Radioactive iodine uptake test shows low iodine uptake, but this test is rarely indicated as it cannot be performed in a nursing patient.

Treatment

Treatment is supportive. In the thyrotoxic phase, beta blockers may be useful for symptomatic therapy, while in the hypothyroid phase thyroxine substitution is indicated.

Prognosis

Many (30-50%) develop permanent hypothyroidism. If not, there’s a 70% risk of relapse after the next pregnancy.