Hashimoto's and Postpartum Thyroiditis
Is There a Cure for this Pregnancy-Related Autoimmune Condition?
Jun 9, 2009
Postpartum thyroiditis is an inflammation of the thyroid gland that appears 1–8 months after giving birth. In developed countries it affects around eight per cent of women who delivered a baby within the previous year. However, this figure is significantly higher in women who have raised levels of circulating thyroid peroxidase autoantibodies (the main indicator of Hashimoto’s disease) when first registering their pregnancy: around 50 per cent of these women will go on to develop postpartum thyroiditis after delivery.(1)
What is Postpartum Thyroiditis?
Postpartum thyroiditis is thought to be an autoimmune condition very similar to Hashimoto’s thyroiditis – the two disorders cannot be distinguished from one another on pathology specimens. It is essentially an autoimmune disorder, characterized by lympocytic infiltration of the thyroid gland, just as in Hashimoto’s disease.
The thyroiditis typically falls into two stages: first it may cause thyrotoxicosis (where stored thyroid hormone leaks out of the inflamed gland and raises hormone levels in the blood), followed by hypothyroidism (low thyroid hormone levels in the blood). This means the woman would feel initially hyperthyroid (and hyperactive) followed by feeling hypothyroid (“slowed down” in every sense – see below).
Can’t the Doctors Diagnose Post-Partum Thyroiditis?
The problem in terms of diagnosing this condition is that the hypothyroid stage of the condition produces symptoms that many doctors would expect to find in a mother who’s just had a baby – she feels exhausted, depressed, constipated, can’t bear exercise, and says her is hair falling out. The doctor, and probably the woman, puts these symptoms down to sleepless nights, or “baby blues”, and may be put onto anti-depressants rather than thyroid medication.
What About the Earlier Hyperthyroid Stage?
Only around a third of women with postpartum thyroiditis pass through both stages, and one-third of patients suffer either one or the other stage, not both. And the thyrotoxic stage is also difficult to diagnose, because it too produces symptoms that are easily attributable to the condition of “new mom”. It occurs 1–4 months after delivery, and symptoms include anxiety, insomnia, palpitations (fast heart rate), fatigue, weight loss, and irritability. It looks like she’s suffering from stress, not a thyroid condition.
So How Do Women Get Diagnosed?
Many women remain undiagnosed, so it is fortunate that the thyroiditis resolves without treatment in most cases. An interested, careful and capable doctor may carry out a thyroid test, and is certainly likely to do so at a patient's request, but the unspecific nature of the symptoms can be extremely misleading. Doctors are more likely to diagnose women who have already been identified as being at risk, including those who:
- already have an identified autoimmune disorder of some form
- have tested positive for anti-thyroid antibodies
- have a history of previous thyroid dysfunction
- have a history of previous postpartum thyroiditis (there is a 20% recurrence rate).
What’s the Treatment?
The hypothyroid stage may be treated with thyroid hormone replacement (Levothyroxine), to re-balance the hormone requirements of the body, and bring rapid relief. Treatment normally continues for around 6–12 months before being tapered off. During this stage thyroid hormone levels must be continuously tested, to check that the woman’s own thyroid is now functioning adequately. If not, lifelong treatment may be required. Around 80 per cent of women regain normal thyroid function, and need only 6–12 months of treatment.
If the hypothyroidism is mild and the woman isn’t experiencing severe or extensive symptoms, she and her doctor may decide that no therapy is necessary.
What Happens if Postpartum Thyroiditis isn’t Treated?
The hypothyroid stage may last 6 –12 months before the thyroid regains normal function. Some women will experience a complete recovery (although they remain at risk of a repeated condition following subsequent pregnancies), while some women (approximately 20 per cent) will develop a permanent hypothyroid condition, because their thyroid is too damaged to regain normal function. It is essential that these women reach a diagnosis, because they will require lifelong treatment with thyroid hormone.
Is There a Preventative Treatment for Postpartum Thyroiditis?
Research suggests that the administration of levothyroxine or iodine during or after pregnancy is not able to reduce the incidence of thyroid dysfunction after delivery (2), although any woman already receiving Levothyroxine treatment for hypothyroidism should continue her treatment throughout pregnancy (possibly increasing the dosage.)
However, selenium has shown interesting results in preventing the disease. In one study, selenium supplementation (after 12 weeks gestation) reduced the number of thyroid dysfunction during the postpartum period, and the number of permanent hypothyroid patients at 12 months after delivery. Furthermore, lower thyroid antibody counts were observed in the Selenium-treated patients during and after the pregnancy. This seems to suggest that in women with high thyroid antibodies, selenium supplementation can prevent the development of postpartum thyroiditis.
Read more about minerals and thyroiditis.
References
- “Postpartum Thyroiditis”; robeto Negro, European Congress of Endocrinology 2009; Endocrine Abstracts (2009) 20; S26.3.
- “Postpartum Thyroiditis”; Stagnaro-Green, Journal of Clinical Endorinology & Metabolism, Vol 87, No.9; 4042–4047.
Notes
- Complement activation in postpartum thyroiditis, Okosieme, Parkes, McCullough, Doukidis, Morgan, Richards and Lazarus; QJ MEd 2002; 95:173–179.
- “Postpartum Thyroiditis”; Stagnaro-Green, Journal of Clinical Endorinology & Metabolism, Vol 87, No.9; 4042–4047.
