Table 2 Unadjusted and adjusted logistic regression models for the likelihood of SARS-CoV-2 test-positivity compared to non-positive (negative and not tested) and test-negative pregnant women in Norway, in relation to characteristics.

From: The association between maternal characteristics and SARS-CoV-2 in pregnancy: a population-based registry study in Sweden and Norway

Characteristics

Test-positive

n = 929¤

Non-positive

n = 80,658

Test-negative

n = 29,699

Test-positive vs. non-positive

Test-positive vs. test-negative

Unadjusted model

Adjusted for age, birth region and education*

Unadjusted model

Adjusted for age, birth region and education*

n (%)

n (%)

n (%)

OR (95%CI)

OR (95%CI)

OR (95%CI)

OR (95%CI)

Background

Age (years)

 < 25

71 (7.6)

6362 (7.9)

1948 (6.6)

0.94 (0.73–1.22)

0.76 (0.58–0.99)

1.20 (0.92–1.55)

0.82 (0.63–1.08)

 25–29

277 (29.8)

24,407 (30.3)

8628 (29.1)

0.96 (0.82–1.12)

0.93 (0.80–1.09)

1.06 (0.90–1.23)

0.98 (0.83–1.15)

 30–34

378 (40.7)

31,980 (39.7)

12,430 (41.9)

Reference

Reference

Reference

Reference

 ≥ 35

203 (21.9)

17,909 (22.2)

6693 (22.5)

0.96 (0.81–1.14)

0.86 (0.72–1.02)

1.00 (0.84–1.19)

0.85 (0.72–1.02)

Parity

 0

329 (35.4)

34,081 (42.3)

11,407 (38.4)

Reference

Reference

Reference

Reference

 1

340 (36.6)

30,690 (38.1)

12,597 (42.4)

1.15 (0.99–1.33)

1.13 (0.96–1.32)

0.94 (0.80–1.09)

0.97 (0.83–1.14)

 2

166 (17.3)

11,548 (14.3)

4347 (14.6)

1.44 (1.19–1.75)

1.27 (1.04–1.55)

1.28 (1.06–1.56)

1.16 (0.95–1.43)

 ≥ 3

99 (10.7)

4339 (5.4)

1348 (4.5)

2.36 (1.88–2.97)

1.46 (1.13–1.88)

2.54 (2.01–3.21)

1.43 (1.10–1.88)

BMI

 < 18.5

23 (2.7)

2448 (3.3)

811 (2.9)

0.87 (0.57–1.32)

0.72 (0.47–1.10)

0.98 (0.64–1.49)

0.76 (0.49–1.17)

 18.5–< 25

472 (55.3)

43,848 (58.6)

16,256 (58.9)

Reference

Reference

Reference

Reference

 25–< 30

232 (27.2)

17,800 (23.8)

6543 (23.7)

1.21 (1.03–1.42)

1.12 (0.95–1.31)

1.22 (1.04–1.43)

1.09 (0.93–1.29)

 30–< 35

90 (10.5)

7145 (9.6)

2629 (9.5)

1.17 (0.93–1.47)

1.09 (0.86–1.37)

1.18 (0.94–1.48)

1.03 (0.61–1.22)

 ≥ 35

37 (4.3)

3557 (4.8)

1343 (4.9)

0.97 (0.69–1.35)

0.95 (0.68–1.34)

0.95 (0.68–1.33)

0.86 (0.83–1.38)

 Missing

75

5860

2117

    

Educational level (years)

 ≤ 9

188 (24.6)

10,580 (14.4)

3217 (11.5)

2.12 (1.78–2.53)

1.41 (1.16–1.71)

2.86 (2.39–3.42)

1.73 (1.42–2.12)

 10–12

179 (23.4)

15,612 (21.1)

5243 (18.7)

1.37 (1.15–1.63)

1.29 (1.08–1.54)

1.67 (1.40–2.00)

1.52 (1.27–1.83)

 > 12)

398 (52.0)

47,494 (64.4)

19,505 (69.7)

Reference

Reference

Reference

Reference

 Missing

164

6972

1734

    

Birth region

 Scandinavia#

461 (49.7)

60,185 (74.7)

23,867 (81.4)

Reference

Reference

Reference

Reference

 Other European c ountry

153 (16.5)

8883 (12.1)

2506 (8.4)

2.25 (1.87–2.70)

2.13 (1.75–2.60)

3.16 (2.62–3.81)

2.75 (2.25–3.36)

 Middle East/Africa

224 (24.1)

5454 (6.8)

1450 (4.9)

5.36 (4.56–6.30)

4.66 (2.86–5.63)

8.00 (6.76–9.47)

5.95 (4.90–7.23)

 Other

90 (9.8)

6047 (7.5)

1867 (6.3)

1.94 (1.55–2.44)

1.83 (1.45–2.32)

2.52 (2.01–3.18)

2.22 (1.75–2.82)

 Missing

1

89

0

    

Smoking status

 Smoker, yes

52 (6.3)

4175 (5.8)

1352 (5.1)

1.10 (0.83–1.46)

1.01 (0.76–1.35)

1.26 (0.95–1.68)

1.00 (0.74–1.34)

 Missing

106

8205

3090

    

Work situation

 Employed

527 (72.6)

58,156 (84.1)

22,378 (87.2)

Reference

Reference

Reference

Reference

 Unemployed

199 (27.4)

10,999 (15.9)

3274 (12.8)

2.00 (1.69–2.35)

1.16 (0.96–1.40)

2.58 (2.18–3.05)

1.30 (1.08–1.58)

 Missing

203

11,503

4047

    

 Co-habits with partner

 No

52 (5.7)

3213 (4.0)

1068 (3.7)

1.44 (1.09–1.91)

0.96 (0.72–1.28)

1.60 (1.20–2.13)

0.88 (0.65–1.19)

 Missing

21

1234

490

    

Pre-existing co-morbidities

Chronic hypertension

3 (0.3)

462 (0.6)

184 (0.6)

0.56 (0.18–1.75)

0.53 (0.17–1.66)

0.52 (0.17–1.63)

0.44 (0.14–1.40)

Diabetes

8 (0.9)

572 (0.7)

215 (0.7)

1.22 (0.60–2.45)

1.35 (0.62–2.54)

1.19 (0.59–2.42)

1.09 (0.53–2.26)

Lung disease/asthma

52 (5.6)

5142 (6.4)

2048 (6.9)

0.87 (0.66–1.15)

0.86 (0.51–1.46)

0.80 (0.60–1.06)

0.98 (0.73–1.30)

Chronic kidney disease

1 (0.1)

472 (0.6)

178 (0.6)

–

–

–

–

Cardiovascular disease

0 (–)

461 (0.6)

173 (0.6)

–

–

–

–

Prior thrombosis

0 (–)

166 (0.2)

56 (0.2)

–

–

–

–

Composite of the above

61 (6.6)

6982 (8.7)

2738 (9.2)

0.74 (0.57–0.96)

0.87 (0.67–1.14)

0.69 (0.53–0.90)

0.80 (0.62–1.05)

Pregnancy related factors

Multiple pregnancy

12 (1.3)

1071 (1.3)

427 (1.4)

0.97 (0.55–1.72)

0.97 (0.55–1.72)

0.90 (0.50–1.60)

0.88 (0.49–1.58)

Pre-eclampsia, HELLP and eclampsia

13 (1.4)

2215 (2.8)

842 (2.8)

0.50 (0.29–0.87)

0.54 (0.31–0.93)

0.49 (0.28–0.84)

0.50 (0.29–0.88)

Gestational diabetes

77 (8.3)

4758 (5.9)

1731 (5.8)

1.44 (1.14–1.82)

1.13 (0.89–1.43)

1.46 (1.15–1.85)

1.09 (0.85–1.39)

In vitro fertilization (IVF)

28 (3.0)

3819 (4.7)

1329 (4.5)

0.63 (0.43–0.91)

0.72 (0.49–1.06)

0.66 (0.45–0.97)

0.80 (0.54–1.17)

  1. ¤8 of 929 (0.9%) positive women had been vaccinated during the study period. *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.
Back to article page