Medicines for Postpartum thyroiditis

What it is

Postpartum thyroiditis is inflammation of the thyroid gland (the gland in the neck that controls metabolism) that develops in the first year after giving birth (and can also follow a miscarriage). It is thought to be an autoimmune condition, and is more common in women who have certain thyroid antibodies or other autoimmune conditions (such as type 1 diabetes). It often follows a characteristic pattern in two phases, though not everyone has both. First, there may be a phase of an overactive thyroid (thyrotoxicosis), as the inflamed gland releases stored thyroid hormone — causing symptoms such as anxiety, irritability, a fast heartbeat, weight loss, tiredness and feeling hot. This is often followed by a phase of an underactive thyroid (hypothyroidism), as the gland becomes depleted — causing symptoms such as tiredness, low mood, weight gain, feeling cold, dry skin and constipation. In many women, the thyroid then recovers and returns to normal, often within about a year, though some are left with a lasting underactive thyroid. Importantly, the symptoms can be mistaken for the normal tiredness and mood changes of the postnatal period, or for postnatal depression, so recognising the possibility of a thyroid problem is important, as it is easily tested for and treated.

How it is treated

Postpartum thyroiditis is diagnosed with thyroid blood tests, and management depends on which phase the woman is in and the severity of symptoms, guided by a doctor. Because the overactive phase is usually temporary and caused by the release of stored hormone (rather than the gland overproducing), it is often not treated with the usual anti-thyroid medicines; instead, if symptoms such as palpitations are troublesome, a medicine to control the heart rate (a beta-blocker) may be used for a while until it settles. The underactive phase is treated, if symptoms warrant, with thyroid hormone replacement (levothyroxine), which relieves the symptoms; because the underactive phase is often temporary, the need for treatment is reviewed over time, and an attempt may later be made to see whether the thyroid has recovered and treatment can be stopped. Monitoring with blood tests tracks the thyroid through the phases and recovery. Because some women are left with a permanent underactive thyroid, or may develop one in future, follow-up thyroid checks are advised, including in future pregnancies (as it can recur). Recognising the condition is key, so that thyroid symptoms after birth are not simply attributed to the postnatal period. The reassuring message is that postpartum thyroiditis is often a temporary condition that is easily tested for and treated according to its phase, with monitoring for recovery — so it is worth checking the thyroid if there are relevant symptoms after having a baby.