Table 3 Characteristics of pregnant admissions by influenza subtype/lineage
Characteristic | A(H1N1)pdm09 | A(H3N2) | B/Yamagata | B/Victoria | P-value |
|---|---|---|---|---|---|
N = 361 | N = 224 | N = 106 | N = 76 | ||
Age group, n (%) | 0.028 | ||||
15–19 years | 11 (3.0) | 10 (4.5) | 2 (1.9) | 2 (2.6) | |
20–24 years | 69 (19.1) | 40 (17.9) | 17 (16.0) | 19 (25.0) | |
25–29 years | 146 (40.4) | 95 (42.4) | 31 (29.2) | 30 (39.5) | |
30–34 years | 91 (25.2) | 51 (22.8) | 31 (29.2) | 23 (30.3) | |
35–39 years | 37 (10.2) | 21 (9.4) | 18 (17.0) | 1 (1.3) | |
40–44 years | 7 (1.9) | 7 (3.1) | 7 (6.6) | 1 (1.3) | |
Age (years), median (range) | 29 (17–44) | 28 (15–43) | 30 (19–42) | 28 (19–45) | 0.004 |
Underlying conditions a, n (%) | |||||
None | 300 (83.1) | 182 (81.3) | 92 (86.8) | 63 (82.9) | 0.666 |
One or more | 61 (16.9) | 42 (18.8) | 14 (13.2) | 13 (17.1) | 0.666 |
Cardiovascular disease | 16 (4.4) | 7 (3.1) | 1 (0.9) | 3 (3.9) | 0.376 |
Chronic obstructive pulmonary disease | 7 (1.9) | 5 (2.2) | 0 (0.0) | 0 (0.0) | 0.276 |
Asthma | 4 (1.1) | 3 (1.3) | 1 (0.9) | 1 (1.3) | 0.988 |
Renal impairment | 31 (8.6) | 20 (8.9) | 7 (6.6) | 8 (10.5) | 0.819 |
Cirrhosis | 3 (0.8) | 2 (0.9) | 2 (1.9) | 1 (1.3) | 0.803 |
Neoplasm | 2 (0.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0.521 |
Trimester of pregnancy, n (%) | 0.005 | ||||
First (0–13 weeks) | 87 (24.1) | 46 (20.5) | 17 (16.0) | 11 (14.5) | |
Second (14–26 weeks) | 167 (46.3) | 81 (36.2) | 44 (41.5) | 40 (52.6) | |
Third (27–42 weeks) | 106 (29.4) | 97 (43.3) | 45 (42.5) | 25 (32.9) | |
Gestational age at admission (weeks), median (range) | 21 (2–41) | 25 (4–40) | 24 (7–41) | 27 (7–38) | 0.017 |
Time from onset of symptoms to swabbing, n (%) | |||||
0–2 days | 263 (72.9) | 167 (74.6) | 57 (53.8) | 42 (55.3) | 0.001 |
3–4 days | 83 (23.0) | 48 (21.4) | 47 (44.3) | 29 (38.2) | |
5–7 days | 15 (4.2) | 9 (4.0) | 2 (1.9) | 5 (6.6) | |
Days from onset of symptoms to swabbing, median (range) | 2 (0–7) | 2 (0–6) | 2 (0–5) | 2 (0–6) | 0.001 |