While many are unaware of the condition, thyroiditis is relatively common – affecting around 200,000 people per year. Thyroiditis causes inflammation of the thyroid gland, located in the neck, which produces the thyroid hormone that controls the metabolism. The condition is not painful, but has a range of negative effects, including anxiety, sudden weight change, palpations, and irritability. Thyroiditis can occur for various reasons – autoimmune disorders, viruses, and more. Because of the variety of causes, thyroiditis has several types that each require specific diagnosis and treatment. One of the lesser-known types of thyroiditis, induced by childbirth delivery, is known as postpartum thyroiditis.
What is postpartum thyroiditis?
Postpartum thyroiditis is a destructive type of thyroiditis that occurs within one year of childbirth. It is caused by a mechanism naturally performed by the body’s immune system, which attacks the thyroid gland after a woman is no longer pregnant and the body returns to its normal immune tolerance.
This process can also occur after spontaneous or induced abortion. Unfortunately, there is no established way to effectively prevent postpartum thyroiditis.
Postpartum thyroiditis usually presents in one of three ways:
- Transient hyperthyroidism – overactive thyroid production
- Transient hypothyroidism – underactive thyroid production
- Transient hyperthyroidism followed by hypothyroidism and then recovery
Most patients experience symptoms of mild hyperthyroidism that are difficult to distinguish from other forms of thyroiditis. These symptoms include rapid heart rate, anxiety, hand tremors, significant weight change, depression, fatigue, and more. These symptoms are not painful and are likely to be confused with general symptoms women experience after giving birth, so many cases of postpartum thyroiditis go undiagnosed and untreated.
Approximately 20-30% of women with postpartum thyroiditis experience a sequence of abnormal thyroid function after childbirth. Many will initially experience hyperthyroidism – overactive thyroid production – 1 to 4 months after delivery. This phase can last anywhere between 2 to 8 weeks.
It is then followed by a phase of hypothyroidism – underactive thyroid production – which can last anywhere between 2 weeks to 6 months. However, about 20-40% of women with postpartum thyroiditis experience hyperthyroidism alone, and another 40-50% experience hypothyroidism alone. Most women have a mildly enlarged thyroid gland during these phases, which later returns to normal in recovery.
Who is affected by postpartum thyroiditis?
Postpartum thyroiditis – compared to other types of thyroiditis – is relatively rare, with only about 7-8% of new moms being affected. However, about 42% of women who were previously diagnosed with postpartum thyroiditis are likely to experience it again after subsequent pregnancies.
Recurrence is likely, and there is a greater risk of hypothyroidism developing down the line, as well as irregular growth of the thyroid gland. After full recovery from postpartum thyroiditis, patients should have their thyroid-stimulating hormone (TSH) levels checked annually, particularly within 5 to 10 years after initial diagnosis.
There are certain populations that are at higher risk of developing postpartum thyroiditis. This includes individuals with:
- Type 1 diabetes mellitus
- A history of high serum TPO antibodies
- A history of postpartum thyroiditis after a previous pregnancy
Many mothers express concern about whether postpartum thyroiditis will affect the health of their newborn child. Fortunately, postpartum thyroiditis does not affect the baby’s health. However, postpartum thyroiditis can decrease milk production, especially in women experiencing a hyperthyroidism phase. Additionally, patients who are receiving treatment for this condition should speak with their doctors about how their medication may affect their breast milk.
Treatment of postpartum thyroiditis varies based on the patient’s thyroid status and symptoms. During a hyperthyroid phase, patients are often treated with beta adrenergic-blocking drugs that reduce blood pressure and manage symptoms of abnormal heart rhythm and nervousness. Such drugs include propranolol, metoprolol, and atenolol. Atenolol, specifically, is contraindicated during breastfeeding and should be avoided if you plan to breastfeed your child.
During a hypothyroid phase, patients are usually treated with thyroid hormone therapy and take hormone supplements. The duration of thyroid hormone therapy is determined by frequent regulation of the patient’s thyroid hormone levels. Usually, hypothyroid symptoms are reversed, but about 25% of patients never fully recover from this phase and need to continue taking supplements for years afterwards.
If you are experiencing symptoms of thyroiditis, whether postpartum or not, contact Dr. Bryll-Perzan at her Katonah office to schedule an appointment at (914) 269-9630.
By Ewelina Bryll-Perzan, MD, Endocrinology, Internal Medicine, Northwell Health Physician Partners, Westchester Health