Table 2. Multivariable models for predicting perinatal transfusion.
| Model 1a (n = 38,005) |
Model 2b (n = 37,930) |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Characteristic | Parameter Estimate | Odds Ratio | OR 95% Confidence Limits |
p-value | Parameter Estimate | Odds Ratio | OR 95% Confidence Limits |
p-value | ||
| Intercept | -4.68 | < .0001 | -5.24 | < .0001 | ||||||
| Antepartum | ||||||||||
| Maternal age <21 or >36, years | 0.23 | 1.26 | 1.09 | 1.46 | .002 | 0.16 | 1.17 | 1.00 | 1.37 | .04 |
| BMI at delivery, kg/m2 | -0.014 | 0.99 | 0.98 | 0.99 | .007 | -0.0153 | 0.99 | 0.98 | 0.99 | .004 |
| 3+ previous term deliveries | 0.65 | 1.92 | 1.60 | 2.34 | < .0001 | 0.6342 | 1.89 | 1.55 | 2.29 | < .0001 |
| Gestational age <37 weeks | 0.63 | 1.85 | 1.59 | 2.14 | < .0001 | - | - | - | - | - |
| African American race | 0.24 | 1.27 | 1.10 | 1.47 | .002 | - | - | - | - | - |
| Insurance: govt vs. private | 0.31 | 1.37 | 1.17 | 1.60 | .0001 | 0.27 | 1.32 | 1.12 | 1.55 | .0009 |
| Insurance: none vs. private | 0.41 | 1.51 | 1.25 | 1.82 | < .0001 | 0.23 | 1.25 | 1.02 | 1.53 | .03 |
| Platelet count <150, (x103) | 0.57 | 1.77 | 1.45 | 2.17 | < .0001 | 0.37 | 1.45 | 1.17 | 1.80 | .0008 |
| Hematocrit <32, (%) | 1.31 | 3.72 | 3.25 | 4.25 | < .0001 | 1.31 | 3.71 | 3.22 | 4.27 | < .0001 |
| No previous CD | 0.44 | 1.56 | 1.34 | 1.82 | < .0001 | 0.61 | 1.83 | 1.45 | 2.32 | < .0001 |
| 2 previous CD | 0.31 | 1.35 | 1.10 | 1.67 | .005 | 0.41 | 1.50 | 1.19 | 1.90 | .0007 |
| 3+ previous CD | 0.45 | 1.57 | 1.16 | 2.13 | .003 | 0.18 | 1.21 | 0.84 | 1.74 | .32 |
| Hx asthma | 0.15 | 1.16 | 0.93 | 1.46 | .20 | - | - | - | - | - |
| Hx heart disease | 0.77 | 2.16 | 1.40 | 3.32 | .0005 | 0.75 | 2.12 | 1.35 | 3.34 | .001 |
| Gest. HTN/Preeclampsia | 0.21 | 1.23 | 1.01 | 1.50 | .04 | 0.35 | 1.42 | 1.18 | 1.71 | .0003 |
| HELLP | 1.11 | 3.03 | 2.00 | 4.57 | < .0001 | - | - | - | - | - |
| Abruption antepartum | 1.18 | 3.26 | 2.60 | 4.10 | < .0001 | - | - | - | - | - |
| Intrapartum | ||||||||||
| Non-elective repeat CD | - | - | - | - | - | 0.54 | 1.72 | 1.39 | 2.14 | < .0001 |
| General anesthesia | - | - | - | - | - | 1.65 | 5.16 | 4.44 | 6.08 | < .0001 |
| Abruption at time of delivery | - | - | - | - | - | 0.96 | 2.61 | 2.06 | 3.32 | < .0001 |
| Multiple gestational | - | - | - | - | - | 0.55 | 1.73 | 1.32 | 2.26 | < .0001 |
| Failure to progress | - | - | - | - | - | 0.50 | 1.65 | 1.32 | 2.08 | < .0001 |
| Eclampsia/HELLP | 1.06 | 2.87 | 1.96 | 4.21 | < .0001 | |||||
| Placenta accreta, increta, or percreta | - | - | - | - | - | 4.52 | 92.02 | 57.36 | 147.63 | < .0001 |
| Antibiotic use | - | - | - | - | - | 0.28 | 1.33 | 1.09 | 1.61 | .004 |
aModel 1: antepartum risk factors; reference group for previous CD = 1
bModel 2: antepartum and intrapartum risk factors