Table 3. The incidence and relative risk ( RR ) for LBW and SGA infants based on maternal serum Zn level.

	Maternal serum Zn levela		P
	Deficiency (n = 247)	Sufficiency (n = 2940)
LBW
Number of LBW	18	65
Incidence (%)	7.3	2.2	<0.001
Univariate RR (95%CI)	3.48 (2.03, 5.96)	1.00	<0.001
Adjusted RR (95%CI)b	3.41 (1.97, 5.91)	1.00	<0.001
SGA
Number of SGA	37	240
Incidence (%)	15.0	8.2	<0.001
Univariate RR (95%CI)	1.98 (1.36, 2.88)	1.00	<0.001
Adjusted RR (95%CI)b	1.93 (1.32, 2.82)	1.00	<0.001

^aDeficiency for serum zinc < 56 μg/dL, and sufficiency for serum zinc ≥ 56 μg/dL.

^bAdjusted for pre-pregnancy BMI, maternal age, gestational week for collecting serum and monthly income per person.