Table 3.
Pregnancy outcomes among propensity score–matched women who received at least 1 dose of the COVID-19 vaccine
| Variables | At least 1 dose during pregnancy (n=133) | Did not receive a vaccine during pregnancy (n=399) | Effect magnitude (95% CI)a | P valuea |
|---|---|---|---|---|
| Intrapartum complications | ||||
| Pyrexia | 5 (3.7) | 4 (1.0) | 3.85 (1.01–14.6) | .046 |
| Suspected chorioamnionitis | 0 (0.0) | 2 (0.5) | NE | NE |
| Placental abruption | 0 (0.0) | 0 (0.0) | NE | NE |
| Postpartum hemorrhage | 13 (9.8) | 36 (9.0) | 1.09 (0.56–2.12) | .795 |
| Birthweight z score | −0.09 (−0.65 to 0.65) | −0.13 (−0.83 to 0.51) | 0.04 (-0.16–0.24) | .427 |
| Small for gestational age at birth | 16 (12.0) | 48 (12.0) | 1.00 (0.55–1.82) | >.999 |
| Fetal abnormalities | 3 (2.2) | 10 (2.5) | 0.89 (0.24–3.31) | .871 |
| Mode of delivery | ||||
| Unassisted vaginal delivery | 71 (53.4) | 221 (55.4) | 0.92 (0.62–1.36) | .687 |
| Instrumental delivery | 21 (15.8) | 42 (10.5) | 1.59 (0.90–2.80) | .106 |
| Cesarean delivery | 41 (30.8) | 136 (34.1) | 0.86 (0.56–1.31) | .490 |
| Stillbirth | 0 (0.0) | 1 (0.2) | NE | NE |
| High-dependency unit admission | 8 (6.0) | 16 (4.0) | 1.53 (0.64–3.66) | .337 |
| Neonatal intensive care unit admission | 7 (5.3) | 20 (5.0) | 1.05 (0.43–2.54) | .909 |
Data are presented as number (percentage) or mean (interquartile range), unless otherwise indicated. Cases and controls were matched 1:3 using propensity scores calculated from the index of multiple deprivation quintile, self-reported ethnicity, antenatal medication, pregestational diabetes mellitus, maternal age, and antihypertensive medication.
CI, confidence interval; MD, mean difference; NE, not estimable; OR, odds ratio.
Blakeway et al. COVID-19 vaccination during pregnancy. Am J Obstet Gynecol 2022.
a
Calculated using generalized estimation equations using matched group identifications as clusters.