Table 2.

Logistic regression models for the use of folic acid supplements before pregnancy^a

	Supplement users, n (%)	Unadjusted models		Adjusted Model 1		Adjusted Model 2
				n = 749, R 2 = 0.22		n = 749, R 2 = 0.22
		OR (95% CI)	p	OR (95% CI)	p	OR (95% CI)	p
Ethnicity
Europe	114 (30.1)	Reference	Reference			Reference
South Asia	23 (11.5)	0.30 (0.19; 0.49)	<0.001	0.40 (0.23; 0.67)	0.001	0.55 (0.31; 0.96)	0.037
Middle East	9 (7.1)	0.18 (0.09; 0.37)	<0.001	0.26 (0.12; 0.56)	0.001	0.42 (0.19; 0.94)	0.034
Africa	7 (11.3)	0.30 (0.13; 0.67)	0.003	0.42 (0.17; 1.08)	0.072	0.71 (0.26; 1.93)	0.50
East Asia	6 (13.6)	0.37 (0.15; 0.89)	0.027	0.60 (0.23; 1.53)	0.28	1.02 (0.38; 2.74)	0.98
Age, years	-	1.04 (1.001; 1.08)	0.046	1.01 (0.97; 1.06)	0.62	1.02 (0.97; 1.07)	0.43
Parity
0	95 (25.2)	Reference		Reference		Reference
≥ 1	64 (14.7)	0.51 (0.36; 0.73)	<0.001	0.65 (0.43; 0.98)	0.04	0.62 (0.40; 0.94)	0.023
Planned pregnancy
No	20 (7.7)	0.23 (0.14; 0.38)	<0.001	0.26 (0.16; 0.44)	<0.001	0.26 (0.15; 0.43)	<0.001
Yes	132 (26.8)	Reference		Reference		Reference
Educational level
High school or less	54 (12.0)	0.32 (0.22; 0.46)	<0.001	0.60 (0.38; 0.93)	0.021	0.65 (0.42; 1.02)	0.058
College or university	105 (29.7)	Reference		Reference		Reference
Norwegian language skills
Poor or quite poor	5 (5.1)	0.15 (0.06; 0.36)	<0.001			0.26 (0.10; 0.72)	0.009
Average or quite good	19 (9.0)	0.27 (0.16; 0.44)	<0.001			0.46 (0.25; 0.83)	0.010
Good	135 (27.1)	Reference				Reference

^aUnadjusted models were performed separately for each variable in the Table. Adjusted Model 1 included ethnicity, age, parity, planning of pregnancy and educational level. Adjusted Model 2 additionally included Norwegian language skills. Statistically significant findings (p < 0.05) are highlighted with bold