Turunen S, Vääräsmäki M, Leinonen M, et al. - Given that 5%–7% of all pregnancies are affected by thyroid dysfunction, researchers herein assessed all singleton pregnancies (N = 736,873) between 2004 and 2016 in Finland obtained from the Finnish Medical Birth Register in order to determine possible modifications in the use of levothyroxine substitution and antithyroid drugs over time in pregnant women. They analyzed data from the Prescription Register and Special Refund Entitlement Register in order to gain information on levothyroxine and antithyroid drug purchases. Findings overall revealed more than a five-fold rise in levothyroxine use during the study period; in 2004, 1.1% of pregnant women received levothyroxine treatment, and by 2016, the prevalence raised to 6.2%. The marked increase in the rate of levothyroxine use in pregnancy suggests an increase in tracing and screening relevant patients as well as a rise in awareness of thyroid disorders on pregnancy and their significance for the pregnancy outcome. Further, the findings suggest a decline in the threshold to treat thyroid disorders.