Table 1.
The efficacy of IIV3-vaccination of pregnant women in preventing fetal death, preterm birth, low birth weight, and small for gestational age infants for mothers who were administered vaccine or placebo on or before 34 weeks gestation.
| IIV3 Vaccine |
Placebo |
|||
|---|---|---|---|---|
| Outcome | Na/Total N (%) | Na/Total N (%) | VE (95%CI) | P |
| Over The Duration Of Mother’s Enrollment Until Delivery | ||||
| Fetal Death b | 16/1025 (1.6) | 13/1010 (1.3) | −21.2 (−150.8, 41.4) | 0.60 |
| Preterm Birth c | 100/958 (10.4) | 80/930 (8.6) | −21.3 (−60.5, 8.3) | 0.17 |
| Low Birth Weight c,d,e | 123/956 (12.9) | 107/928 (11.5) | −11.1 (−42.3, 12.5) | 0.38 |
| Small for Gestational Age (SGA) c,e,f,g | 156/955 (16.3) | 138/928 (14.9) | −9.9 (−35.6, 11.0) | 0.38 |
| In Women At Risk During The Influenza Seasons | ||||
| Fetal Death b | 13/924 (1.4) | 11/908 (1.2) | −16.1 (−157.9, 47.7) | 0.71 |
| Preterm Birth c | 77/885 (8.7) | 61/856 (7.1) | −17.2 (−14.4, 40.1) | 0.22 |
| Low Birth Weight c,d,e | 105/883 (11.9) | 85/854 (10.0) | −27.7 (−67.3, 2.5) | 0.20 |
| Small for Gestational Age (SGA) c,e,f,g | 149/882 (16.9) | 130/854 (15.2) | −9.9 (−11.8, 27.4) | 0.34 |
a
N = number of fetal outcomes.
b
N = total number of subjects without regard to their gestational stage at vaccine or placebo administration.
c
Using only live births; excluded 1 subject whose gestational age of 21 weeks at birth was incongruent with her birth weight of 3185 g.
d
LBW is < 2500 g.
e
Birth weight missing for two subjects who were excluded.
f
<10th percentile weight for GA.
g
Sex was missing for one subject and thus percent weight for gestational age could not be computed for that subject.