| |
Adjusted odds ratio (95% CI) a
|
|---|
| |
Any influenza
|
A(H1N1)pdm09
|
A(H3N2)
|
B/Yamagata
|
B/Victoria
|
|---|
|
Characteristic
|
N = 825
|
N = 361
|
N = 224
|
N = 106
|
N = 76
|
|---|
|
Age (in years) b
|
1.02 (1.00–1.04)
|
1.03 (1.01–1.06)
|
1.00 (0.97–1.03)
|
1.09 (1.04–1.13)
|
0.96 (0.91–1.00)
|
|
Trimester
|
|
First (0–13 weeks)
|
1
|
1
|
1
|
1
|
1
|
|
Second (14–26 weeks)
|
1.19 (0.92–1.53)
|
1.17 (0.82–1.66)
|
0.89 (0.58–1.35)
|
1.34 (0.75–2.51)
|
2.28 (1.10–4.74)
|
|
Third (27–42 weeks)
|
1.12 (0.86–1.46)
|
0.82 (0.56–1.19)
|
1.23 (0.82–1.87)
|
1.57 (0.86–2.88)
|
1.58 (0.72–3.44)
|
|
Underlying conditions
|
|
No
|
1
|
1
|
1
|
1
|
1
|
|
Yes
|
1.56 (1.16–2.08)
|
1.78 (1.19–2.67)
|
1.91 (1.25–2.93)
|
1.24 (0.66–2.34)
|
2.01 (0.39–3.15)
|
- aAdjusted for age, trimester, comorbidity, hospital admission in the previous 12 months, time to swab, and season-week
- bComparison group was influenza-negative pregnant women
