Fig. 2

Median urinary iodine concentration (IUC μg/L) of pregnant women for studies conducted before 1995, between 1995–2004 and 2005–2020 (the dashed vertical line shows adequate median UIC during pregnancy; a [b, c] denotes median with IQR, a [±b] denotes mean and standard deviation, and a [b – c] median with the range). NS national survey, ss sub-national survey