Postpartum thyroiditis

Postpartum thyroiditis is a painless inflammation of the thyroid gland that occurs in a small number of women, usually four to 12 months after childbirth. The cause isn't known. You're at greater risk of postpartum thyroiditis if you have an immune system disorder or a prior history of thyroiditis.

In the first phase of this condition, you experience signs and symptoms of overactive thyroid (hyperthyroidism). This usually lasts two to four months. Treatment may include beta blockers to reduce symptoms of overactive thyroid.

In the second phase, you have signs and symptoms of underactive thyroid (hypothyroidism). This also lasts two to four months. A doctor may confirm a diagnosis by a blood test that measures thyroid-stimulating hormone (TSH). Treatment may include thyroid replacement hormone.

In most cases, thyroid function returns to normal within 12 to 18 months after onset of symptoms. However, some women may develop long-term hypothyroidism and need lifelong thyroid hormone replacement therapy.

Rarely, hypothyroidism after childbirth is caused by Sheehan's syndrome, also called postpartum hypopituitarism. This condition may occur in women who have severe blood loss during childbirth resulting in failure of the anterior pituitary gland.