Table 2. Meta-analysis of chorioamnionitis and dichotomous variables.
| Meta-analysis | CA type | k | OR | 95% CI | Z | p | Heterogeneity | ||
|---|---|---|---|---|---|---|---|---|---|
| Q | p | I2 (%) | |||||||
| Antenatal Corticosteroids (any dosage) | Clinical | 6 | 1.19 | 0.79 to 1.79 | 0.84 | 0.402 | 73.5 | <0.001 | 93.2 |
| Histological | 18 | 1.28 | 1.00 to 1.64 | 1.96 | 0.050 | 85.3 | <0.001 | 80.1 | |
| Any type | 25 | 1.25 | 1.03 to 1.52 | 2.21 | 0.027 | 162.0 | <0.001 | 85.2 | |
| Cesarean section | Clinical | 7 | 0.33 | 0.19 to 0.57 | -3.93 | <0.001 | 278.3 | <0.001 | 97.8 |
| Histological | 14 | 0.34 | 0.23 to 0.49 | -5.52 | <0.001 | 86.8 | <0.001 | 85.0 | |
| Any type | 22 | 0.34 | 0.26 to 0.45 | -7.33 | <0.001 | 368.3 | <0.001 | 94.3 | |
| Maternal diabetes | Any type | 2 | 0.71 | 0.53 to 0.95 | -2.29 | 0.022 | 0.1 | 0.775 | 0.0 |
| Preeclampsia | Histological | 5 | 0.20 | 0.16 to 0.25 | -13.20 | <0.001 | 1.4 | 0.844 | 0.0 |
| PROM | Clinical | 2 | 5.99 | 2.52 to 14.26 | 4.05 | <0.001 | 5.0 | 0.025 | 80.0 |
| Histological | 9 | 3.37 | 2.21 to 5.16 | 5.61 | <0.001 | 87.6 | <0.001 | 90.9 | |
| Any type | 11 | 3.78 | 2.61 to 5.47 | 7.04 | <0.001 | 99.0 | <0.001 | 89.9 | |
| Small for gestational age | Clinical | 2 | 0.48 | 0.16 to 1.49 | -1.47 | 0.204 | 0.01 | 0.925 | 0.0 |
| Histological | 9 | 0.32 | 0.18 to 0.56 | -4.04 | <0.001 | 90.0 | <0.001 | 91.1 | |
| Any type | 11 | 0.35 | 0.22 to 0.55 | -4.44 | <0.001 | 90.1 | <0.001 | 88.9 | |
| Early onset sepsis | Clinical | 7 | 4.51 | 3.29 to 6.19 | 9.36 | <0.001 | 6.1 | 0.409 | 2.1 |
| Histological | 10 | 3.68 | 2.53 to 5.36 | 6.81 | <0.001 | 21.2 | 0.012 | 57.6 | |
| Any type | 17 | 4.15 | 3.26 to 5.28 | 11.55 | <0.001 | 27.5 | 0.036 | 41.9 | |
| Late onset sepsis | Clinical | 4 | 1.30 | 0.86 to 1.98 | 1.23 | 0.219 | 12.4 | 0.006 | 75.9 |
| Histological | 11 | 1.40 | 1.05 to 1.86 | 2.31 | 0.021 | 75.5 | <0.001 | 86.8 | |
| Any type | 16 | 1.35 | 1.09 to 1.67 | 2.78 | 0.005 | 89.1 | <0.001 | 83.2 | |
| Mortality | Clinical | 7 | 1.66 | 1.26 to 2.18 | 3.65 | <0.001 | 17.1 | 0.009 | 64.9 |
| Histological | 13 | 1.47 | 1.15 to 1.87 | 3.17 | 0.002 | 37.3 | <0.001 | 67.9 | |
| Any type | 21 | 1.52 | 1.25 to 1.85 | 4.15 | <0.001 | 81.1 | <0.001 | 75.3 | |
CA: chorioamnionitis; k: number of included studies; OR: odds ratio; PROM: premature rupture of membranes; SGA: small for gestational age. An OR higher than 1 indicates that CA is a risk factor for the outcome, an OR below one indicates that CA is a protective factor for the outcome. Statistically significant odds ratios are marked in bold.