Postpartum thyroiditis, which looks exactly like new parenthood
It affects about one woman in twenty in the first year, and its symptoms are the ones everyone dismisses.
Fatigue. Anxiety. Palpitations. Low mood. Hair loss. Weight change. Every one of those is what a new parent is told to expect, and every one of them is also how postpartum thyroiditis presents.
It affects roughly 5% of women in the first year after birth, about one in twenty. Some reviews put the range at 5% to 10%.
Typically, an exacerbation induces destructive thyrotoxicosis followed by transient hypothyroidism, known as postpartum thyroiditis. Late development of permanent hypothyroidism is found frequently and patients should be followed up once every one to two years.
So it usually runs overactive first, then underactive, and sometimes it does not come all the way back. That is why follow-up matters even after it settles.
It is not Graves disease, and the difference is treatable in one direction only. Quoted: Postpartum thyroiditis typically occurs 1-4 months after parturition whereas Graves' disease develops at 4-12 months postpartum.
Postpartum thyroiditis is destructive and self-limiting, so antithyroid drugs do nothing for it. Graves disease is productive and requires treatment. Getting the two confused causes harm in either direction.
Higher risk if you have thyroid antibodies, type 1 diabetes, another autoimmune condition, or a previous episode. In a Dutch cohort of women with type 1 diabetes, overt postpartum thyroid dysfunction occurred in 15.9%, about three times the background rate.