Table 3.
Predictors of anemia, iron and zinc status in pregnant women, controlling for trimester: linear regression analyses (dichotomous and ordinal independent variables) and ANCOVA analyses (non-ordinal, multi-categorical independent variables) 1.
| Variable | Hemoglobin (g/dL) | Ferritin, Adjusted for APP (µg/L) 2,3 | Soluble Transferrin Receptor (mg/L) 2 | Zinc, Adjusted for APP (µg/dL) 3 | ||||
|---|---|---|---|---|---|---|---|---|
| Mean (95% CI) | p | Geometric Mean (95% CI) | p | Geometric Mean (95% CI) | p | Mean (95% CI) | p | |
| Current pregnancy, trimester 4 | 0.64 | <0.01 | <0.01 | <0.01 | ||||
| First | NA | NA | NA | NA | ||||
| Second | 9.7 (9.5, 9.9) | 32.0 (29.2, 35.1) | 7.0 (6.6, 7.5) | 55.5 (54.3, 56.7) | ||||
| Third | 9.6 (9.5, 9.8) | 25.4 (23.8, 27.0) | 8.1 (7.8, 8.5) | 50.9 (50.1, 51.7) | ||||
| Season | <0.01 | 0.14 | 0.04 | 0.29 | ||||
| June–September (Lean, rainy season) | 9.5 (9.1, 9.9) | 0.01 | 24.0 (20.1, 28.8) | 0.15 | 8.1 (7.2, 9.2) | 0.04 | 54.0 (51.7, 56.2) | 0.71 |
| October–February (Post-harvest, cool season) | 9.1 (8.6, 9.5) | <0.01 | 25.5 (20.5, 31.6) | 0.05 | 8.8 (7.7, 10.2) | <0.01 | 50.9 (48.2, 53.7) | 0.37 |
| March–May (Hot season) | 10.5 (10.0, 11.1) | REF | 34.4 (26.7, 44.3) | REF | 6.3 (5.3, 7.5) | REF | 51.9 (48.7, 55.1) | REF |
| Demographic and socio-economic characteristics | ||||||||
| Adolescent | <0.01 | <0.01 | 0.50 | 0.64 | ||||
| Yes | 9.2 (8.9, 9.5) | 32.1 (28.0, 36.8) | 8.0 (7.3, 8.7) | 52.7 (51.0, 54.4) | ||||
| No | 9.7 (9.6, 9.8) | 26.5 (25.0, 28.1) | 7.7 (7.4, 8.1) | 52.3 (51.6, 53.0) | ||||
| Marital status | 0.25 | 0.95 | 0.02 | 0.79 | ||||
| Monogamous | 9.7 (9.5, 9.8) | REF | 27.1 (25.4, 28.8) | REF | 7.8 (7.4, 8.1) | REF | 52.3 (51.5, 53.1) | REF |
| Polygamous, first wife | 9.6 (9.3, 9.9) | 0.55 | 27.7 (24.0, 32.0) | 0.76 | 7.0 (6.4, 7.7) | 0.04 | 52.0 (50.2, 53.8) | 0.78 |
| Polygamous, ≥2nd wife | 9.5 (9.2, 9.7) | 0.10 | 27.1 (24.2, 30.3) | 0.99 | 8.2 (7.7, 8.9) | 0.13 | 52.7 (51.3, 54.2) | 0.57 |
| Ethnicity, matrnal | 0.17 | 0.05 | 0.05 | 0.25 | ||||
| Hausa | 9.7 (9.5, 9.8) | REF | 28.0 (26.5, 29.6) | REF | 7.6 (7.3, 8.0) | REF | 52.5 (51.8, 53.2) | REF |
| Tuareg | 9.5 (9.1, 9.8) | 0.36 | 23.1 (19.6, 27.2) | 0.03 | 8.4 (7.6, 9.4) | 0.09 | 50.6 (48.5, 52.7) | 0.10 |
| Other (minority) | 9.2 (8.7, 9.7) | 0.09 | 23.8 (18.6, 30.5) | 0.21 | 8.9 (7.6, 10.4) | 0.05 | 52.4 (49.4, 55.5) | 0.95 |
| Education, maternal | 0.91 | 0.19 | <0.01 | 0.20 | ||||
| None | 9.6 (9.5, 9.8) | REF | 26.8 (25.0, 28.7) | REF | 8.0 (7.6, 8.4) | REF | 51.9 (51.0, 52.8) | REF |
| Koranic schooling | 9.6 (9.4, 9.9) | 0.87 | 26.6 (23.9, 29.6) | 0.90 | 7.9 (7.4, 8.5) | 0.76 | 52.6 (51.2, 54.0) | 0.36 |
| Primary (1–6 years) | 9.5 (9.3, 9.8) | 0.52 | 31.1 (27.2, 35.6) | 0.05 | 6.9 (6.3, 7.5) | <0.01 | 53.9 (52.1, 55.6) | 0.04 |
| Secondary (7–14 years) | 9.6 (9.2, 10.0) | 0.87 | 25.7 (20.9, 31.5) | 0.70 | 7.4 (6.5, 8.4) | 0.26 | 51.8 (49.2, 54.4) | 0.97 |
| Obstetric history | ||||||||
| Primigravida | 0.01 | <0.01 | 0.56 | 0.72 | ||||
| Yes | 9.3 (9.0, 9.6) | 34.9 (30.1, 40.4) | 8.0 (7.2, 8.8) | 52.6 (50.8, 54.5) | ||||
| No | 9.7 (9.5, 9.8) | 26.4 (25.1, 27.9) | 7.7 (7.4, 8.1) | 52.3 (51.5, 53.0) | ||||
| Attended ANC in last pregnancy | 0.63 | 0.35 | 0.01 | 0.11 | ||||
| Yes | 9.7 (9.5, 9.8) | 26.6 (25.1, 28.1) | 7.6 (7.3, 7.9) | 52.4 (51.7, 53.2) | ||||
| No | 9.8 (9.4 , 10.1) | 24.2 (20.1, 29.1) | 9.1 (8.0, 10.2) | 50.5 (48.2, 52.8) | ||||
| Result of last pregnancy, n (%) | <0.01 | <0.01 | <0.01 | 0.12 | ||||
| Miscarriage, stillbirth | 9.5 (8.9, 10.0) | 0.32 | 20.3 (15.4, 26.7) | <0.01 | 9.3 (7.8, 11.1) | <0.01 | 54.1 (50.6, 57.7) | 0.24 |
| Live birth, child deceased | 9.0 (8.7, 9.4) | <0.01 | 21.2 (17.9, 25.0) | 0.04 | 9.1 (8.2, 10.1) | 0.02 | 54.0 (51.9, 56.2) | 0.07 |
| Live birth, child living | 9.7 (9.6, 9.9) | REF | 27.3 (25.8, 28.9) | REF | 7.5 (7.3, 7.9) | REF | 52.0 (51.2, 52.7) | REF |
| Knowledge, attitudes and practices | ||||||||
| Attended ANC in current pregnancy | 0.88 | 0.15 | 0.31 | 0.19 | ||||
| Yes | 9.6 (9.5, 9.8) | 27.9 (26.3, 29.7) | 7.7 (7.3, 8.0) | 52.0 (51.2, 52.8) | ||||
| No | 9.6 (9.4, 9.9) | 25.6 (23.1, 28.3) | 8.0 (7.5, 8.5) | 53.0 (51.7, 54.3) | ||||
| IFA supplement coverage | 0.45 | 0.27 | 0.02 | 0.54 | ||||
| Yes | 9.6 (9.4, 9.8) | 27.8 (26.0, 29.8) | 7.5 (7.2, 7.9) | 52.1 (51.3, 53.0) | ||||
| No | 9.7 (9.5, 9.8) | 26.0 (23.8, 28.5) | 8.2 (7.7, 8.7) | 52.6 (51.5, 53.8) | ||||
| IFA supplement adherence | 0.82 | 0.44 | <0.01 | 0.45 | ||||
| Yes | 9.6 (9.4, 9.8) | 27.8 (25.6, 30.2) | 7.4 (7.0, 7.8) | 52.0 (51.0, 53.0) | ||||
| No | 9.6 (9.5, 9.8) | 26.6 (24.8, 28.6) | 8.1 (7.7, 8.5) | 52.5 (51.6, 53.4) | ||||
| Utilization of mosquito net | 0.02 | 0.46 | 0.29 | 0.52 | ||||
| Yes | 9.7 (9.6, 9.8) | 26.9 (25.4, 28.6) | 7.7 (7.4, 8.0) | 52.2 (51.4, 53.0) | ||||
| No | 9.4 (9.1, 9.6) | 28.3 (25.2, 31.8) | 8.0 (7.5, 8.7) | 52.7 (51.3, 54.2) | ||||
| Quantity of food consumed during pregnancy | 0.99 | 0.05 | 0.42 | 0.29 | ||||
| Increased | 9.6 (9.4, 9.9) | 0.92 | 27.1 (24.2, 30.4) | 0.23 | 7.6 (7.0, 8.1) | 0.22 | 52.7 (51.3, 54.1) | 0.20 |
| Decreased | 9.6 (9.5, 9.8) | 0.94 | 28.7 (26.7, 30.8) | 0.02 | 7.7 (7.3, 8.1) | 0.30 | 52.6 (51.7, 53.5) | 0.14 |
| No change | 9.6 (9.4, 9.8) | REF | 24.7 (22.4, 27.3) | REF | 8.0 (7.5, 8.6) | REF | 51.5 (50.2, 52.7) | REF |
| Number of meals consumed during pregnancy | 0.37 | 0.30 | 0.08 | 0.13 | ||||
| Increased | 9.8 (9.5, 10.0) | 0.20 | 27.3 (24.2, 30.9) | 0.49 | 7.3 (6.7, 7.9) | 0.02 | 53.1 (51.6, 54.6) | 0.09 |
| Decreased | 9.6 (9.4, 9.8) | 0.97 | 28.4 (26.3, 30.7) | 0.12 | 7.7 (7.3, 8.1) | 0.21 | 52.7 (51.8, 53.7) | 0.08 |
| No change | 9.6 (9.4, 9.8) | REF | 26.0 (23.8, 28.3) | REF | 8.1 (7.6, 8.5) | REF | 51.5 (50.4, 52.6) | REF |
| Adequate minimum dietary diversity—women (MDD-W) | 0.46 | 0.70 | <0.01 | 0.62 | ||||
| Yes | 9.5 (9.3, 9.8) | 27.8 (24.7, 31.3) | 7.1 (6.6, 7.7) | 52.6 (51.1, 54.2) | ||||
| No | 9.6 (9.5, 9.8) | 27.1 (25.6, 28.7) | 7.9 (7.6, 8.2) | 52.2 (51.5, 53.0) | ||||
| Consumed vitamin A rich foods in past 24 h | 0.17 | 0.59 | 0.23 | 0.92 | ||||
| Yes | 9.6 (9.5, 9.7) | 27.1 (25.6, 28.6) | 7.8 (7.5, 8.2) | 52.3 (51.6, 53.0) | ||||
| No | 9.8 (9.5, 10.1) | 28.2 (24.6, 32.4) | 7.4 (6.8, 8.1) | 52.4 (50.6, 54.1) | ||||
| Consumed animal source foods in past 24 h | 0.49 | 0.30 | 0.29 | 0.93 | ||||
| Yes | 9.7 (9.5, 9.9) | 26.3 (24.1, 28.6) | 7.6 (7.2, 8.0) | 52.3 (51.3, 53.4) | ||||
| No | 9.6 (9.4, 9.8) | 27.8 (26.0, 29.7) | 7.9 (7.5, 8.2) | 52.3 (51.4, 53.1) | ||||
| Geophagy (consumed clay) | <0.01 | <0.01 | <0.01 | 0.02 | ||||
| Yes | 9.1 (8.7, 9.4) | 17.2 (14.6, 20.4) | 10.4 (9.3, 11.6) | 50.0 (47.9, 52.1) | ||||
| No | 9.7 (9.5, 9.8) | 28.5 (27.0, 30.1) | 7.5 (7.2, 7.9) | 52.6 (51.8, 53.3) | ||||
| Nutritional and health status | ||||||||
| Malaria antigenemia (elevated HRP2) | <0.01 | <0.01 | 0.59 | 0.23 | ||||
| Yes | 9.0 (8.7, 9.3) | 33.8 (29.3, 39.0) | 8.0 (7.2, 8.7) | 51.3 (49.5, 53.1) | ||||
| No | 9.7 (9.6, 9.9) | 26.5 (25.1, 27.9) | 7.7 (7.4, 8.1) | 52.5 (51.7, 53.2) | ||||
1 APP, acute phase proteins; ANC, antenatal care; IFA, iron and folic acid; HRP2, histidine rich protein II; REF, reference; 2 Ferritin and sTfR: logarithmically transformed; 3 Ferritin and zinc: continuous adjustment to the 10th percentile of study specific C-reactive protein and α-1-acid glycoprotein concentrations; 4 Data exclude participants in first trimester, n = 1.