Table 4.

Rates of high adherence to micronutrient supplementation before and during pregnancy by maternal characteristics and adjusted OR (95% CI) for factors associated to the high adherence among Chinese women in Shaanxi, 2010-2013*

Characteristics	n	FA		Iron		Calcium		MMN
		High adherence (%)†	Adjusted OR (95% CI)	High adherence (%)	Adjusted OR (95% CI)	High adherence (%)	Adjusted OR (95% CI)	High adherence (%)	Adjusted OR (95% CI)
Sociodemographic characteristics (Model 1)‡
Age (years)
<25	9458	5.3	Ref	0.4	Ref	11.2	Ref	1.7	Ref
25–34	16 764	8.7	1.30 (1.11 to 1.52)§	0.7	1.49 (1.18 to 1.88)§	12.4	1.03 (0.94 to 1.12)	3.3	1.38 (1.12 to 1.71)§
≥35	2456	6.3	1.22 (0.98 to 1.51)	0.6	1.54 (0.80 to 2.99)	8.6	0.71 (0.62 to 0.81)§	2.3	1.24 (0.84 to 1.84)
Education
Junior high school or below	17 724	4.9	Ref	0.4	Ref	9.9	Ref	1.6	Ref
Senior high school	5741	7.3	1.38 (1.18 to 1.61)§	0.9	2.00 (1.36 to 2.96)§	13.8	1.32 (1.22 to 1.42)§	2.8	1.51 (1.21 to 1.88)§
College and beyond	5213	15.9	2.59 (2.21 to 3.05)§	1.2	1.69 (1.12 to 2.54)§	15.5	1.45 (1.31 to 1.60)§	6.2	2.65 (2.14 to 3.28)§
Residence
Rural	19 301	5.9	Ref	0.4	Ref	10.6	Ref	2.1	Ref
Urban	9377	10.4	1.72 (1.08 to 2.72)§	1.1	1.88 (1.17 to 3.01)§	14.0	1.21 (0.90 to 1.62)	3.9	1.30 (0.82 to 2.06)
Per capita annual household income (RMB)
Low	9689	5.0	Ref	0.4	Ref	10.6	Ref	1.8	Ref
Medium	9402	6.4	1.07 (0.94 to 1.23)	0.5	1.06 (0.74 to 1.54)	11.7	1.08 (0.99 to 1.19)	2.2	1.18 (0.96 to 1.45)
High	9538	10.7	1.27 (1.11 to 1.45)§	1.0	1.56 (1.05 to 2.32)§	12.8	1.09 (0.96 to 1.24)	4.0	1.39 (1.11 to 1.76)§
Birth history and antenatal care information (Model 2)¶
Parity
Primiparous	16 803	9.2	Ref	0.7	Ref	12.8	Ref	3.2	Ref
Multiparous	11 875	4.8	0.70 (0.58 to 0.84)§	0.5	0.90 (0.61 to 1.34)	10.1	1.02 (0.94 to 1.11)	1.9	0.88 (0.72 to 1.07)
pregnancy consultation
No	21 385	5.6	Ref	0.5	Ref	10.7	Ref	2.3	Ref
Yes	7293	12.6	1.91 (1.71 to 2.14)§	1.0	1.40 (1.21 to 1.96)§	14.7	1.22 (1.10 to 1.34)§	3.8	1.40 (1.17 to 1.67)§
The number of antenatal visits
<5	8608	3.8	Ref	0.3	Ref	7.6	Ref	15.4	Ref
≥5	20 070	8.9	1.59 (1.35 to 1.87)§	0.8	1.66 (1.18 to 2.34)§	13.4	1.41 (1.25 to 1.60)§	26.4	1.33 (1.09 to 1.62)§
Type of hospitals for antenatal visits
Township hospitals	3405	5.9	Ref	0.5	Ref	9.6	Ref	1.7	Ref
County hospitals or above	25 273	7.6	1.14 (0.94 to 1.37)	0.6	1.26 (0.79 to 2.01)	12.0	1.10 (0.94 to 1.29)	2.8	1.14 (0.90 to 1.46)

*N=28 678. The number of missing values for supplementation of FA, iron, calcium and MMN were 49, 34, 130 and 50. Adjusted OR and 95% CI were derived from multivariable GEE models with random effects at county level.

†High adherence to FA supplementation was defined as starting from the periconceptional period with ≥180 days of use; high adherence to iron supplementation was considered as starting from the first trimester with ≥90 days of use; high adherence to calcium supplementation was considered as starting from the second trimester with ≥90 days of use; high adherence to MMS was defined as starting from the first trimester with ≥90 days of use.

‡Model 1 adjusted for the sociodemographic characteristics including maternal age, education, residence and income and the OR and 95% CI of these characteristics was derived from model 1.

§Model 2 adjusted for all variables in model 1 plus parity and antenatal care characteristics, and the OR and 95% CI of parity and antenatal care characteristics were derived from model 2.

¶Refers to p<0.05.

FA, folic acid;GEE, generalised estimating equation; MMN, multiple-micronutrients.