Kurajoh M, et al. - Researchers investigated the predictive value of inferior thyroid artery peak systolic velocity (ITA-PSV) for an increase in levothyroxine (LT4) dosage in pregnant women with Hashimoto’s thyroiditis. They conducted a retrospective longitudinal observational study including 22 women with Hashimoto’s thyroiditis who were planning and later got or were confirmed as pregnant. Observations support that, independent of thyroid stimulating hormone (TSH) level, ITA-PSV significantly predicts an increase in LT4 dosage in pregnant patients with Hashimoto’s thyroiditis, while significantly improved predictability was noted with ITA-PSV plus TSH vs TSH alone. As per these results, ITA-PSV indicates residual thyroid function in pregnant patients with Hashimoto’s thyroiditis and is valuable for assessing the necessity for increased thyroid hormone production.