Table 3. Consequences of pandemic A/H1N1 2009 influenza vaccination on pregnancy outcomes.
| A/H1N1 2009 influenza vaccinated pregnant women | Non-vaccinated pregnant women | p-value | |
| n = 320 | n = 557 | ||
| Gestational age (weeks) at delivery,edian (IQR) | 39.5 (38.6–40.9) | 39.4 (38.7–40.6) | - |
| Delivery <37 weeks, n (%) | 22 (6.9) | 41 (7.4) | 0.80 |
| Onset of labour, n (%) | |||
| Spontaneous | 210 (66.7) | 367 (66.4) | |
| Induction | 71 (22.5) | 130 (23.5) | 0.92 |
| Caesarean | 34 (10.8) | 56 (10.1) | |
| Fever during labour, n (%) | 26 (8.1) | 53 (9.5) | 0.51 |
| Mode of delivery, n (%) | |||
| Spontaneous vaginal delivery | 210 (66.7) | 379 (68.3) | |
| Instrumental vaginal delivery | 34 (10.8) | 47 (8.5) | 0.53 |
| Caesarean section | 71 (22.5) | 129 (23.2) | |
| Delivery hemorrhage, n (%) | |||
| None | 239 (90.5) | 432 (90.9) | |
| <1 liter | 23 (8.7) | 35 (7.4) | - |
| >1 liter | 2 (0.8) | 8 (1.7) | |
| Birth weight, g | |||
| Mean | 3296.1 | 3282.0 | |
| <2500, n (%) | 22 (6.9) | 33 (6.0) | |
| [2500–4000[, n (%) | 273 (85.9) | 485 (87.2) | 0.81 |
| ≥4000, n (%) | 23 (7.2) | 38 (6.8) | |
| Apgar score <7 at 5 min, n (%) | 1 (0.3) | 5 (0.9) | 0.42† |
| Infants outcome | |||
| Alive at birth | 317 (99.7) | 552 (99.3) | |
| Dead before labour | 1 (0.3) | 3 (0.5) | - |
| Dead during labour | 0 (0.0) | 1 (0.2) | |
| Transfer to neonatal intensive care unit‡ | 31 (9.8) | 61 (11.1) | 0.58 |
| Pregnancy loss | 1 (0.3) | 3 (0.5) | 0.24 |
| Fetal malformation | 4 (1.25) | 3 (0.5) | 0.26 |
| Pre eclampsia | 1 (0.3) | 2 (0.3) | 1 |
†
Fisher’s exact test;
‡
First infant for multiple birth.