Table 5.

Association between maternal selenium blood concentration in mid-pregnancy and gestational length^*

(β-Coefficients and 95 % confidence intervals)

	Unadjusted			Adjusted†
	β ‡	95 % CI	P	β ‡	95 % CI	P
All subjects (n 2638)
Blood Se concentration§	0·12	−0·27, 0·50	0·55	−0·02	−0·41, 0·38	0·94
Spontaneous deliveries (n 2177)
Blood Se concentration§	0·10	−0·28, 0·49	0·60	0·03	−0·36, 0·42	0·89

^*Multiple linear regression analysis of blood Se concentrations in relation to gestational length in days for 2638 participants in the Norwegian Mother and Child Cohort Study. Blood Se concentration was measured in whole blood collected in gestational week 17−18 in a subsample of 2638 of the 72 025 participating mothers.

^†Adjusted for: maternal age, parity, smoking habits, alcohol consumption during pregnancy, maternal education and BMI.

^‡ β per standard deviation (23·4 μg/l) of blood Se concentration.

^§Measured in μg/l.