TABLE 2.
Frequency and adjusted ORs of mode of delivery and birthweight at time of induction compared to delivery at later GA
| Variable | aORa | 95% CI | |
|---|---|---|---|
| Cesarean delivery | |||
| 39 wk’ GA | |||
| Induction (n = 42,769) | 26.2% | 0.90 | 0.88–0.91 |
| Expectant (n = 278,578) | 28.4% | Referent | |
| 40 wk’ GA | |||
| Induction (n = 52,383) | 31.0% | 0.88 | 0.86–0.92 |
| Expectant (n = 74,860) | 33.7% | Referent | |
| 41 wk’ GA | |||
| Induction (n = 28,325) | 36.0% | 0.89 | 0.83–0.95 |
| Expectant (n = 4744) | 39.0% | Referent | |
| Operative vaginal deliveryb | |||
| 39 wk’ GA | |||
| Induction (n = 31,574) | 14.3% | 1.11 | 0.97–1.15 |
| Expectant (n = 199,390) | 12.9% | Referent | |
| 40 wk’ GA | |||
| Induction (n = 36,129) | 15.5% | 1.16 | 1.12–1.22 |
| Expectant (n = 49,628) | 13.4% | Referent | |
| 41 wk’ GA | |||
| Induction (n = 18,044) | 15.7% | 1.30 | 1.15–1.47 |
| Expectant (n = 2893) | 12.0% | Referent | |
| Birthweight >4000 g | |||
| 39 wk’ GA | |||
| Induction (n = 42,947) | 6.4% | 0.33 | 0.30–0.35 |
| Expectant (n = 279,733) | 11.9% | Referent | |
| 40 wk’ GA | |||
| Induction (n = 56,606) | 11.0% | 0.62 | 0.59–0.64 |
| Expectant (n = 75,224) | 16.5% | Referent | |
| 41 wk’ GA | |||
| Induction (n = 28,470) | 16.7% | 0.75 | 0.68–0.81 |
| Expectant (n = 4772) | 20.2% | Referent |
aOR, adjusted odds ratio; CI, confidence interval; GA, gestational age.
a
Multivariable logistic regression controlling for: maternal age, race/ethnicity, number of prenatal care visits, gestational weight gain, cigarette smoking during pregnancy, education; referent comparison group composed of women who did not have induction of labor (ie, expectantly managed) and delivered at later GA
b
Operative vaginal delivery examined among women who did not have cesarean deliveries as denominator.
Source: National Center for Health Statistics (2005).19