Table 3.
Obstetric and maternal outcomes among the study groups
| Covid-19 two-dose vaccinated n = 1094 |
Covid-19 booster vaccinated n = 626 |
p value | Covid-19 unvaccinated n = 863 |
p value | |
|---|---|---|---|---|---|
| Gestational age at delivery | 39.4 ± 1.5 | 39.1 ± 1.5 | < 0.01 | 39.4 ± 1.5 | < 0.01 |
| Gestational age at delivery < 34 weeks | 12 (1.1%) | 6 (1%) | 0.79 | 5 (0.6%) | 0.40 |
| Gestational age at delivery < 37 weeks | 36 (3.3%) | 25 (4%) | 0.45 | 37 (4.3%) | 0.78 |
| Induction of labor | 61 (5.6%) | 28 (4.5%) | 0.32 | 35 (4.1%) | 0.69 |
| Oxytocin augmentation of labor | 686 (62.7%) | 362 (57.8%) | 0.05 | 507 (58.7%) | 0.72 |
| Epidural analgesia | 634 (58%) | 353 (56.4%) | 0.53 | 382 (44.3%) | < 0.01 |
| Meconium-stained amniotic fluid | 186 (17%) | 83 (13.3%) | 0.04 | 194 (22.5%) | < 0.01 |
| Chorioamnionitis | 23 (2.1%) | 13 (2.1%) | 0.97 | 20 (2.3%) | 0.76 |
| Cesarean delivery | 144 (13.2%) | 105 (16.8%) | 0.04 | 91 (10.5%) | < 0.01 |
| Planned cesarean delivery | 68 (6.2%) | 63 (10.1%) | < 0.01 | 35 (4.1%) | < 0.01 |
| In labor cesarean | 63 (5.8%) | 32 (5.1%) | 0.57 | 40 (4.6%) | 0.67 |
| Home/car delivery | 11 (1%) | 10 (1.6%) | 0.28 | 14 (1.6%) | 0.97 |
| Vacuum-assisted delivery | 80 (7.3%) | 43 (6.9%) | 0.73 | 47 (5.4%) | 0.26 |
| Hospitalization length, days | 1.9 ± 1 | 1.9 ± 1.1 | 0.42 | 1.7 ± 1 | 0.01 |
| Prolonged hospital stay | 6 (0.5%) | 7 (1.1%) | 0.19 | 2 (0.2%) | 0.03 |
| Episiotomy | 97 (8.9%) | 62 (9.9%) | 0.48 | 107 (12.4%) | 0.13 |
| Maternal ICU admissions | 0 (0%) | 1 (0.2%) | 0.19 | 2 (0.2%) | 0.76 |
| Postpartum hemorrhage | 96 (8.8%) | 41 (6.5%) | 0.10 | 77 (8.9%) | 0.09 |
| Placental abruption | 10 (0.9%) | 9 (1.4%) | 0.32 | 23 (2.7%) | 0.11 |
| Hemoglobin drop, g/dL | 1.3 ± 1 | 1.3 ± 1 | 0.81 | 1.2 ± 1 | 0.31 |
| Hemoglobin drop > 4 g/dL | 26 (2.4%) | 12 (1.9%) | 0.53 | 21 (2.4%) | 0.50 |
| Puerperal fever | 54 (4.9%) | 24 (3.8%) | 0.29 | 35 (4.1%) | 0.83 |
| Blood products transfusion | 8 (0.7%) | 13 (2.1%) | 0.01 | 8 (0.9%) | 0.06 |
| Composite adverse maternal outcome | 144 (13.2%) | 68 (10.9%) | 0.16 | 113 (13.1%) | 0.19 |
Data are mean ± standard deviation; number (%)
ICU intensive care unit
aComposite adverse maternal outcome was defined as one of the following: cesarean delivery, prolonged hospitalization, postpartum hemorrhage, blood products transfusion, maternal ICU admissions, chorioamnionitis, and endometritis