Table 1.

Treatment adjustment according to thyroid hormone levels.

Newborn age	12 h of life	2 days of life	5 days of life	20 days of life	48 days of life	2 months and 10 days	3 months	4 months	8 months	1 year
TSH levels (mU/L)	108	23.3	3.08	0.24	0.16	0.27	0.82	0.84	1.06	3
Reference values (−2 SD to +2 SD) (18):	2.43–24.03	1.4–13.1	0.6–6.82	0.58–5.57	0.58–5.57	0.58–5.57	0.58–5.57	0.58–5.57	0.58–5.57	0.57–5.54
Free-LT4 Levels (pmol/L)	7.6	9.5	17.4	20.4	18.6	16.9	16.0	14.7	15.0	18.4
Reference values (−2 SD to +2 SD) (18):	12.12–56.54	12.12–56.54	12.32–42.54	12.81–44.33	12.81–44.33	13.41–36.83	13.41–36.83	13.82–31.39	13.82–31.39	14.14–28.22
Levothyroxine dosage (µg/kg/day)		15	15	10.5	6	3	End of treatment	No treatment needed	No treatment needed	No treatment needed

SD, standard deviation.