Table 6.
Association of preterm birth and smoking with maternal congestive heart failure (n = 1,446)
| Univariate | Multivariate 1 | Multivariate 2 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| HR | 95 % CI | HR | 95 % CI | HR | 95 % CI | ||||
| Term birth | Ref | Ref | Ref | ||||||
| Any preterm birth | 2.99 | 2.34 | 3.83 | 2.50 | 1.92 | 3.24 | 2.27 | 1.74 | 2.94 |
| Preterm birth by severity | |||||||||
| Late preterm birth | 2.44 | 1.75 | 3.41 | 2.20 | 1.57 | 3.07 | 1.89 | 1.49 | 2.80 |
| Moderately preterm birth | 3.06 | 1.79 | 5.21 | 2.67 | 1.56 | 4.56 | 2.47 | 1.36 | 4.55 |
| Extremely preterm birth | 4.47 | 2.98 | 6.71 | 3.32 | 2.07 | 5.31 | 3.08 | 1.94 | 5.08 |
| Preterm birth by onset | |||||||||
| Spontaneous preterm birth | 2.42 | 1.76 | 3.31 | 2.26 | 1.64 | 3.10 | 2.03 | 1.48 | 2.80 |
| Indicated preterm birth | 4.29 | 3.02 | 6.10 | 2.99 | 2.03 | 4.39 | 2.74 | 1.87 | 4.03 |
| Preterm birth by number | |||||||||
| 1 preterm birth | 2.81 | 2.17 | 3.65 | 2.40 | 1.83 | 3.15 | 2.20 | 1.67 | 2.88 |
| ≥2 preterm births | 5.24 | 2.79 | 9.83 | 3.59 | 1.88 | 6.87 | 3.02 | 1.58 | 5.78 |
| Smokinga | |||||||||
| Never smoking during pregnancy | Ref | Ref | |||||||
| Smoking before last pregnancy | 3.59 | 2.48 | 5.20 | 2.50 | 1.70 | 3.68 | |||
| Smoking during last pregnancy | 2.97 | 2.44 | 3.61 | 2.38 | 1.93 | 2.95 | |||
Multivariate 1: Preterm birth adjusted for maternal age at delivery, country of birth, socioeconomic status, number of births, SGA, pregestational and gestational diabetes
Multivariate 2: Variables in Multivariate 1 + maternal smoking during pregnancy
a: Multivariate 2 adjusted for any preterm birth