Table 3.
Unadjusted and adjusted logistic regression models for the likelihood of being tested (positive or negative) compared to not tested for SARS-CoV-2 in pregnant women in Norway in relation to characteristics.
| Characteristics, n (%) | Tested n = 30,628 (24.6%) |
Not tested n = 50,959 (75.4%) |
Unadjusted model OR (95%CI) |
Adjusted for age, birth region and education* OR (95%CI) |
|---|---|---|---|---|
| Background | ||||
| Age (years) | ||||
| < 25 | 2019 (6.6) | 4414 (8.7) | 0.70 (0.66–0.74) | 0.87 (0.80–0.98) |
| 25–29 | 8905 (29.1) | 15,779 (31.0) | 0.86 (0.83–0.89) | 0.93 (0.88–0.98) |
| 30–34 | 12,808 (41.8) | 19,550 (38.4) | Reference | Reference |
| ≥ 35y | 6896 (22.5) | 11,216 (22.0) | 0.94 (0.90–0.97) | 0.92 (0.87–0.98) |
| Parity | ||||
| 0 | 11,736 (38.3) | 22,674 (44.5) | Reference | Reference |
| 1 | 12,937 (42.2) | 18,093 (35.5) | 1.38 (1.34–1.43) | 1.38 (1.33–1.42) |
| 2 | 4508 (14.7) | 7201 (14.1) | 1.21 (1.16–1.26) | 1.23 (1.17–1.29) |
| ≥ 3 | 1447 (4.7) | 2991 (5.9) | 0.93 (0.87–1.00) | 1.07 (0.99–1.14) |
| BMI | ||||
| < 18.5 | 834 (2.9) | 1637 (3.5) | 0.84 (0.77–0.92) | 0.93 (0.86–1.02) |
| 18.5–< 25 | 16,728 (58.8) | 27,592 (58.4) | Reference | Reference |
| 25–< 30 | 6775 (23.8) | 11,257 (23.8) | 0.99 (0.96–1.03) | 1.02 (0.98–1.05) |
| 30–< 35 | 2719 (9.6) | 4516 (9.6) | 0.99 (0.96–1.10) | 1.03 (0.98–1.08) |
| ≥ 35 | 1380 (4.9) | 2214 (4.7) | 1.03 (0.96–1.10) | 1.07 (1.00–1.15) |
| Missing | 2192 | 3743 | ||
| Educational level (years) | ||||
| ≤ 9 | 3405 (11.9) | 7363 (16.1) | 0.65 (0.62–0.70) | 0.71 (0.68–0.75) |
| 10–12 | 5422 (18.9) | 10,369 (22.7) | 0.74 (0.71–0.76) | 0.76 (0.73–0.78) |
| > 12 | 19,903 (69.3) | 27,989 (61.2) | Reference | Reference |
| Missing | 1898 | 5238 | ||
| Birth region | ||||
| Scandinavia# | 24,337 (79.5) | 36,309 (71.3) | Reference | Reference |
| Other European country | 2659 (8.7) | 6377 (12.5) | 0.62 (0.59–0.65) | 0.67 (0.64–0.71) |
| Middle East/Africa | 1674 (5.5) | 4004 (7.9) | 0.62 (0.59–0.67) | 0.76 (0.71–0.81) |
| Other | 1936 (6.3) | 4201 (8.3) | 0.69 (0.65–0.73) | 0.74 (0.69–0.78) |
| Missing | 22 | 68 | ||
| Smoking status | ||||
| Smoker | 1404 (5.1) | 2823 (6.2) | 0.82 (0.77–0.88) | 0.94 (0.88–1.01) |
| Missing | 3196 | 5115 | ||
| Work situation | ||||
| Employed | 22,905 (86.8) | 35,778 (82.2) | Reference | Reference |
| Unemployed | 3473 (13.2) | 7725 (17.8) | 0.70 (0.67–0.73) | 0.88 (0.84–0.92) |
| Missing | 4250 | 7456 | ||
| Co-habits with partner | ||||
| No | 1120 (3.7) | 2145 (4.3) | 0.86 (0.80–0.93) | 0.99 (0.92–1.07) |
| Missing | 511 | 855 | ||
| Pre-existing co-morbidities | ||||
| Chronic hypertension | 187 (0.6) | 278 (0.6) | 1.12 (0.93–1.35) | 1.13 (0.93–1.36) |
| Diabetes | 223 (0.7) | 357 (0.7) | 1.04 (0.88–1.23) | 1.04 (0.88–1.23) |
| Lung disease/asthma | 2100 (6.9) | 3094 (6.1) | 1.14 (1.08–1.21) | 1.09 (1.03–1.16) |
| Chronic kidney disease | 179 (0.6) | 294 (0.6) | 1.01 (0.84–1.22) | 1.01 (0.84–1.22) |
| Cardiovascular disease | 173 (0.5) | 288 (0.6) | 1.00 (0.83–1.21) | 0.93 (0.77–1.13) |
| Prior thrombosis | 56 (0.2) | 110 (0.2) | 0.85 (0.61–1.17) | 0.79 (0.57–1.10) |
| Composite of the above | 2799 (9.1) | 4244 (8.3) | 1.11 (1.05–1.16) | 1.07 (1.01–1.12) |
| Pregnancy related factors | ||||
| Multiple pregnancy | 439 (1.4) | 644 (1.3) | 1.14 (1.01–1.28) | 1.13 (1.00–1.28) |
| Pre-eclampsia, HELLP and eclampsia | 855 (2.8) | 1373 (2.7) | 1.04 (0.95–1.13) | 1.03 (0.94–1.12) |
| Gestational diabetes | 1808 (5.9) | 3027 (5.9) | 0.99 (0.94–1.05) | 1.07 (1.01–1.14) |
| In vitro fertilization (IVF) | 1357 (4.4) | 2490 (4.9) | 0.90 (0.84–0.97) | 0.82 (0.76–0.88) |
*For the association between age and tested, the adjusted model included the covariate education and birth region. For the association between education and tested, the adjusted model included the covariates age and birth region. For the association between birth region and tested, the adjusted model included the covariates age and education. #Sweden, Norway, Denmark.