Post-partum thyroiditis is the commonest endocrine disorder associated with pregnancy, occurring in 8%1of the post partum population during 1st year after childbirth. It is an autoimmune disorder precipitated by the postpartum immunological rebound that follows the immunosuppression during pregnancy. After one episode of postpartum thyroiditis, there is a 70%2chance of recurrence with subsequent pregnancies. Though there have been case reports of postpartum thyroiditis after spontaneous abortion, here we present a case of three documented episodes of recurrent postpartum thyroiditis following early pregnancy loss, which we believe has not been reported previously.
A 32-year-old female presented with palpitations and lethargy three months after her first pregnancy loss. Laboratory examination revealed transient hyperthyroidism followed by hypothyroidism at 6 months. Within a month whilst she was hypothyroid, she became pregnant. She continued to remain euthyroid whilst on treatment. TPO antibody was not detected. She had an uncomplicated delivery and three months after the delivery, she again had symptoms of palpitations, hot flushes and weight loss due to hyperthyroidism, which resolved within three months. Eighteen months later, she had a second miscarriage and within a month developed hyperthyroidism followed by hypothyroidism, and then recovered. Radionuclide scans revealed complete absence of thyroidal pertechnetate accumulation.
Two episodes of painless thyroiditis within few months of pregnancy loss in this woman suggest that the immunological changes of a short-term gestation may be sufficient to lead to thyroiditis. Moreover these women are as prone to recurrence as woman with post-partum thyroiditis after childbirth.
As these women may be attempting to conceive again it is important to advise avoidance of conception until normalization of thyroid function. Evaluation of thyroid function is routinely warranted in women with a history of post partum thyroid dysfunction to optimize maternal thyroid status during early pregnancy, before the development of fetal thyroid function.