What Is Postpartum Thyroiditis?
Postpartum thyroiditis is inflammation of the thyroid following delivery of a baby. Postpartum thyroiditis can result in hyperthyroidism at first and ultimately produces hypothyroidism. The cause of postpartum thyroiditis is thought to be an autoimmune disease similar to Hashimoto thyroiditis. The two entities cannot be distinguished pathologically. In the United States, a small percentage of pregnant women develop postpartum thyroiditis.
Certain risk factors may help predict who is at an increased risk for developing postpartum thyroiditis, according to the American Thyroid Association (ATA).* These include:
- Presence of antithyroid antibodies prior to pregnancy
- Type 1 diabetes
- History of prior thyroid dysfunction
- Family history of thyroid dysfunction
When the thyroid becomes inflamed, it will first emit large quantities of thyroid hormone into the bloodstream producing hyperthyroidism. During this phase, most women are unaware of any symptoms, which are often mild and short-lived. However, once this initial phase passes, a woman either recovers completely or has sustained damage to her thyroid. If the thyroid gland was damaged, this damage—together with a depleted reservoir of thyroid hormones—can lead to hypothyroidism (underactive thyroid). This condition, too, may also clear up or result in permanent hypothyroidism requiring hormone replacement.
The following are the most common symptoms associated with the hyperthyroidism that accompany postpartum thyroiditis. Symptoms may include:
- Feeling warm
- Muscle weakness
- Feeling tremulous
- Rapid heartbeat
- Loss of concentration
- Weight loss
The most common symptoms of hypothyroidism that accompany postpartum thyroiditis are:
- Feeling tired
- Memory loss
- Cold weather intolerance
- Muscle cramps
- Weight gain
Postpartum thyroiditis symptoms may not appear until several months after childbirth. Symptoms are also often mistaken for normal signs of recovery from childbirth. Always consult your physician for a diagnosis.
Diagnostic procedures used to detect postpartum thyroiditis depend on the phase of the disease. A blood test to measure levels of thyroid hormones (T3 and T4) and thyroid-stimulating hormones can usually determine whether the mother has hypothyroidism or hyperthyroidism. However, treatment is based on severity of symptoms rather than lab values in this illness.
Most women with postpartum thyroiditis do not need treatment during either the hyperthyroid or hypothyroid phases of their illness. Treatment depends on the phase of the disease and the degree of symptoms the woman is experiencing. Women with significant symptoms of hyperthyroidism are usually treated with beta blockers, medicines to slow down the heart rate and lessen symptoms.
Women with significant symptoms of hypothyroidism are treated with thyroid hormone replacement. According to the ATA, it is very important for women to have ongoing thyroid monitoring, since 80 percent of women with this diagnosis will have normal thyroid function within 12 to 18 months after the onset of symptoms and can stop treatment under their physician's supervision.