Why carry out this study?

Hypothyroidism (HT) is a common disease in the US, more prevalent in women than men and associated with adverse maternal and fetal outcomes if left untreated during pregnancy.

Clinical guidelines recommend screening for HT among women who are pregnant or planning a pregnancy and, if diagnosed with HT, treatment with levothyroxine in consultation with an endocrinologist who monitors thyroid-stimulating hormone (TSH) levels.

This study describes treatment of pregnant women diagnosed with HT and examines the concurrence between observed TSH levels and clinical practice guidelines’ recommended levels.

What was learned from the study?

Among women treated with levothyroxine, 52.61% had a last recorded TSH value consistent with American Thyroid Association (ATA) guidelines, 23.85% were undertreated, 1.03% were overtreated, and 22.52% did not have TSH monitored during their pregnancy.

A large percentage of the women, including many treated with levothyroxine, was not treated in a manner consistent with clinical guidelines.

There were significant differences in general health and comorbidities between pregnant women treated with levothyroxine and those untreated.