Clinical features and risk factors for severe and critical pregnant women with 2009 pandemic H1N1 influenza infection in China

Table 1 Demographic characteristics, underlying conditions, symptoms and lab findings of 394 pregnant patients*

Variables	Value
Age, years
median years (IQR)	25 (23-28)
≤ 20 y (%)	23/375 (6.1)
20-35 y (%)	331/375 (88.3)
> 35 y (%)	21/375 (5.6)
Han Chinese (%)	371/393 (94.4)
Job
Farmer (%)	200/389 (51.4)
Unemployed (%)	84/389 (21.6)
Others (%)†	105/389 (27.0)
BMI, median (IQR)	26.0 (23.4-29.3)
≤ 25.0 (%)	99/243 (40.7)
25-30 (%)	99/243 (40.7)
30-35 (%)	35/243 (14.4)
> 35 (%)	10/243 (4.1)
Gestational age§
1^st trimester (0-14 week) (%)	20/394 (5.1)
2^nd trimester (15-27 week) (%)	88/394 (22.3)
3^rd trimester (≥ 28 week) (%)	286/394 (72.6)
Chronic pre-existing disease
Respiratory diseases** (%)	11/388 (2.8)
Cardiovascular diseases*** (%)	13/393 (3.3)
Diabetes mellitus (%)	4/394 (1.0)
Cancer or hematological diseases (%)	3/394 (0.8)
Immune suppressed (%)	1/390 (0.3)
Pneumonia (%)	351/390 (90.0)
Symptoms and Lab findings
T ≥ 38°C (%)	340/374 (90.9)
Cough (%)	372/393 (94.7)
Dyspnoea (%)	199/393 (50.6)
Hemoptysis (%)	55/392 (14.0)
Pleural effusion (%)	44/226 (19.5)
CNS symptom ※ (%)	48/392 (12.2)
WBC (×10⁹/L)	7.4 ± 3.7
Platelet (×10⁹/L)	169.0 ± 65.7
CK > 200 u/L (%)	77/306 (19.5)
CRP (mg/L)	42 (16-101)
ESR (mm/h)	35 (23-50)
PaO₂/FiO₂, median (IQR)	154.7 (89.5-320.5)
APACHE II scores, median (IQR)	7 (4-11)

IQR, interquartile range; BMI, body mass index; APACHE II, acute physiology and chronic health evaluation II
* Data are presented as no./total no., if otherwise stated. Percentages are based on women with complete information in the respective categories
Nineteen patients missed the detailed information. Percentages may not total 100 because of rounding
† Other job included student (in two patients), teacher (in twelve), babysitter (in one), catering (in one), business service (in eleven), worker (in nine), migrant laborer (in ten), herdsman (in one), professional staff member (in seventeen), retired (in one), health care worker (in three), other detailed (in thirty-seven)
§ The median gestational age was 32 weeks (IQR, 26-37 weeks)
** included asthma, COPD, active tuberculosis and other bronchial disease
***included coronary heart disease, chronic congestive heart failure, valvular disease
※ CNS system symptoms: refers to one or more of the following symptoms: insomnia, restlessness, hallucination, headache, dizziness and abnormal behaviour