Variable Vaccinated women N=1019, n (%) Unvaccinated women N=253, n (%)
Maternal age (years) 15-19 20-24 25-29 >30 85 (8.3) 289 (28.3) 390 (38.2) 255 (25.0) 44 (17.3) 97 (38.3) 68 (26.8) 44 (17.3)
Maternal age, mean (SD) 26.2 ± 4.9 24.5± 4.9
Race/ethnicity Caucasian Aboriginal/TSI Others 850 (83.4) 15 (1.4) 154 (15.1) 204 (80.6) 8 (3.1) 41 (16.2)
Household annual income in AUD <40,000 40,001-70,000 70,001-105,000 >105,001 Missing 212 (20.8) 221 (21.6) 283 (27.7) 293 (28.7) 10 (0.9) 81 (32.0) 62 (24.5) 44 (17.3) 61 (24.1) 5 (1.9)
Maternal education ≤ Secondary school qualification Diploma/certificate Bachelor’s or higher degree Missing 436 (42.7) 365 (35.8) 216 (21.2) 2 (0.2) 119 (47.0) 90 (35.5) 42 (16.6) 2 (0.7)
Total years of formal education, mean (SD) 13.4 ± 2.4 13.0 ± 2.6
Moderate exercise during 1st trimester/pre-pregnancy ≥ 4 per week 1–3 per week Never Missing 126 (12.3) 493 (48.3) 393 (38.5) 7 (0.6) 22 (8.7) 118 (46.6) 110 (43.4) 3 (1.1)
Gravidity >1 296 (29.0) 57(22.5)
Asthma 146 (14.3) 31 (12.5)
Assisted reproductive technology (IVF) 60 (5.8) 10 (3.9)
Pre-pregnancy BMI (kg/m2) <18.5 (Under) 18.5-24 (Normal) 25-29.9 (Overweight) ≥ 30 (Obese) 16 (1.5) 389 (38.1) 274 (26.8) 340 (33.3) 9 (3.5) 110 (43.4) 81 (32.0) 53 (20.9)
Pre-pregnancy BMI (kg/m2), mean (SD) 28.2 ± 7.1 26.7± 6.7
Smoking status at 9-16 weeks’ gestation Current smoker Quit during pregnancy Non-smoker Missing 87 (8.5) 112 (10.9) 815 (79.9) 5 (0.4) 34 (13.4) 25 (9.8) 192 (75.8) 2 (0.7)
Illicit drug use during 1st trimester/pre-pregnancy 51 (5.0) 26 (10.2)
Multivitamin and mineral supplements use Pre-conception and 1st trimester 1st trimester None Missing 248 (24.3) 548 (53.7) 217 (21.3) 6 (0.5) 37 (14.6) 133 (52.5) 82 (32.4) 1 (0.4)
Psychological measures at 9-16 weeks’ gestation Edinburgh Perinatal Depression Scale (EPDS) scores, mean (SD) State and trait anxiety (STAI) scores, mean (SD) Perceived stress scale (PSS) scores, mean (SD Missing 5.3 ± 4.8 33.2 ± 11.2 12.9 ± 6.5 30 (2.9) 5.7± 4.5 33.8 ± 11.0 13.5 ± 6.4 12 (4.7)
Gestational week of vaccine administration, mean (SD) 30.3 ± 2.8 NA
Gestational week of vaccine administration, median (IQR) 30 (26 -34) NA
Received influenza vaccination during pregnancy 555 (54.4) 42 (16.6)