What Is Postpartum Thyroiditis?Postpartum thyroiditis is an inflammation of the thyroid that initially occurs in the first year after childbirth, miscarriage, or induced abortion. It's considered a variation of autoimmune thyroiditis, also known as Hashimoto's thyroiditis.
Who Is at Risk of Postpartum Thyroiditis?Any woman who has been pregnant can have postpartum thyroiditis, and the condition is fairly common. It's estimated that approximately 7% of women develop the condition. The risks are higher for women with the following conditions and thyroid markers:
- Up to 25% of women with type 1 diabetes develop postpartum thyroiditis.
- Up to 25% of women with elevated antithyroid antibodies -- with normal thyroid hormone levels -- may develop postpartum thyroiditis.
- Up to 50% of women with elevated anti-peroxidase (anti-TPO) antibodies may develop postpartum thyroiditis
- Postpartum thyroiditis is also far more common in a woman who has had a previous episode of the condition.
Can You Prevent Postpartum Thyroiditis? Details from UpToDateIn digging deep for an answer to this question, I turned to UpToDate -- a trusted electronic reference that is used by many physicians treating women who develop thyroid problems after pregnancy.
According to UpToDate, selenium supplementation may help prevent postpartum thyroiditis in some women. Here, an excerpt from the resource:
"Selenium supplementation may decrease inflammatory activity in pregnant women with autoimmune hypothyroidism, and may reduce the risk of postpartum thyroiditis in women who are positive for thyroid peroxidase (TPO) antibodies. This was illustrated in a trial of 151 TPO-positive women randomly assigned to receive selenium (200 mcg daily) or placebo (beginning at about the 12th week of gestation). Postpartum thyroiditis occurred in 22 of 77 women (29%) in the selenium group, compared to 36 of 74 (49%) in the placebo group . The routine clinical application of this supplementation requires further study."
Should you take selenium supplements? That's a question for you and you doctor to decide, and that conversation should take place prior to you trying them for yourself.
The Typical Course of Postpartum ThyroiditisThe most common course for postpartum thyroiditis is mild hypothyroidism which begins two to six months after delivery, and then resolves as the thyroid normalizes. The next most common presentation is mild hyperthyroidism, which begins one to four months after delivery, after which the thyroid normalizes.
In some women, mild hyperthyroidism begins one to four months after delivery and lasts two to eight weeks. It then shifts into a period of mild hypothyroidism for several weeks to several months, and then the thyroid normalizes.
While some cases of after postpartum thyroiditis resolve over time, there is a strong risk of continued thyroid disease. It's estimated that as many as half the patients with postpartum thyroiditis will, within four to eight years, develop persistent hypothyroidism, a goiter, or both.
Symptoms of Postpartum ThyroiditisThere are a number of symptoms of postpartum thyroiditis that can appear during both the hyperthyroid and hypothyroid phases of the condition. These include:
- Decreased milk volume in breastfeeding women
- Hair loss
- Goiter (enlarged thyroid gland) that is painless
- Depression, moodiness
The symptoms during the hypothyroid phase of postpartum thyroiditis are milder versions of general hypothyroidism symptoms, including sluggishness, dry skin, difficulty losing weight (or weight gain), constipation, low body temperature, and puffiness in the eyes, face and hands.
How Is Postpartum Thyroiditis Diagnosed?Postpartum thyroiditis is usually diagnosed by blood tests. In the hyperthyroid phase, blood tests typically show low TSH, high-normal or elevated T4 and T3. In the hypothyroid phase, TSH is elevated, and T4 is low or low-normal. Antithyroid peroxidase (anti-TPO) antibody concentrations are likely to be elevated in the majority of postpartum thyroiditis sufferers, especially during the hypothyroid phase.
In some cases of postpartum thyroiditis, an ultrasound is performed, and typically will show enlargement of the thyroid gland.
Postpartum thyroiditis and autoimmune Graves' disease can both cause hyperthyroidism after childbirth. While postpartum thyroiditis is a far more common cause of hyperthyroidism, it is still important not to miss Graves' disease. UpToDate offers details on how to distinguish postpartum thyroiditis from Graves' hyperthyroidism, which can also begin during the postpartum period:
"The key differences are that hyperthyroidism in postpartum thyroiditis is usually mild (both clinically and biochemically), thyroid enlargement is minimal, and Graves' ophthalmopathy is absent. In contrast, women with Graves' hyperthyroidism are more symptomatic, have higher serum thyroid hormone concentrations, more thyroid enlargement, and may have Graves' ophthalmopathy. The distinction between postpartum thyroiditis and Graves' hyperthyroidism may be difficult unless the woman has new-onset ophthalmopathy. The two disorders can often be distinguished by reevaluation in three to four weeks. By that time, most women with postpartum thyroiditis will have improved, whereas those with Graves' hyperthyroidism will be unchanged or worse."In some cases, a radioiodine uptake test is done to differentiate postpartum thyroiditis from Graves' disease. (Note, however, that this test is not performed if a woman is breastfeeding.)