Table 2 Results of trace element analysis at term and at 6 months gestation corrected age (GCA).

Analyte	Time of sampling	Observed values
		Mean (SD)	Median	Range	n
Plasma zinc, µmol/l	At term	12.0 (2.6)	11.8	5.0–20.5	58
	At 6 months GCA	13.8 (2.5)*	13.2	9.1–22.7	54
Plasma copper, µmol/l	At term	10.1 (2.6)	9.4	5.8–17.0	51
	At 6 months GCA	19.2 (3.6)*	19.1	10.5–26.4	56
Plasma selenium, µmol/l	At term	0.49 (0.15)	0.49	0.21–0.88	62
	At 6 months GCA	0.72 (0.14)*	0.73	0.49–1.09	56
Whole blood selenium, µmol/l	At term	0.87 (0.21)	0.83	0.48–1.49	56
	At 6 months GCA	0.94 (0.12)	0.95	0.68–1.23	50
Red cell selenium, µmol/l	At term	1.68 (0.40)	1.67	0.7–2.55	56
	At 6 months GCA	1.33 (0.19)*	1.31	0.92–1.89	51
Whole blood manganese, nmol/l	At term	320 (189)	281	110–1129	54
	At 6 months GCA	211 (68)†	202	86–400	50

*p = 0.001, †p = 0.002, second vs first test.