Table 1.
Maternal and obstetrical characteristics for singleton term pregnancies and normal neonatal outcomes for women with trial of labor after cesarean and nulliparous women.
| Characteristic | TOLAC* n=2,892 |
Nulliparous Women n=56,301 |
P |
|---|---|---|---|
| Age, years (mean ± SD) | 28.3 ± 5.7 | 24.9 ± 5.9 | <.001 |
| Race (%) | <.001 | ||
| White | 43.0 | 49.7 | |
| Black | 23.7 | 21.0 | |
| Hispanic | 20.3 | 16.7 | |
| Asian/Pacific Islander | 5.3 | 5.2 | |
| Other/Unknown | 7.6 | 7.4 | |
| Prepregnancy BMI, kg/m2 (mean ± SD) | 26.5 ± 6.7 | 24.2 ± 5.6 | <.001 |
| Admission BMI, kg/m2 (mean ± SD) | 31.9 ± 6.5 | 30.1 ± 5.9 | <.001 |
| Gestational age at delivery, weeks (mean ± SD) | 39.1 ± 1.1 | 39.4 ± 1.3 | <.001 |
| Pre-existing diabetes (%) | 1.6 | 0.7 | <.001 |
| Gestational diabetes (%) | 4.9 | 3.6 | <.001 |
| Chronic hypertension (%) | 2.1 | 1.1 | <.001 |
| Gestational hypertension (%) | 1.8 | 3.7 | <.001 |
| Preeclampsia/HELLP (%) | 3.4 | 5.0 | <.001 |
| Eclampsia (%) | 0.1 | 0.1 | 0.439 |
| Cervical dilation at admission, cm - Median (10th, 90th percentile) | 3 (0.5, 6) | 3 (1, 6) | 0.004 |
| Cervical effacement at admission (%) - Median, % (10th, 90th percentiles) | 80 (30, 100) | 80 (50, 100) | <.001 |
| Station at admission (%) - Median (10th, 90th percentiles) | −2 (−3, 0) | −2 (−3, 0) | <.001 |
| Epidural (%) | 47.9 | 58.6 | <.001 |
| Induction (%) | 23.4 | 44.1 | <.001 |
| Oxytocin for spontaneous labor (%) | 52.4 | 64.3 | <.001 |
| Oxytocin for induced labor (%) | 89.8 | 91.6 | 0.099 |
| Cesarean delivery (%) | 57.7 | 19.0 | <.001 |
| Estimated Blood Loss, mL (mean ± SD) | 574 ± 273 | 426 ± 304 | <.001 |
*
Women (parity=1) with one prior cesarean delivery and no prior vaginal deliveries attempting vaginal birth after cesarean.
Abbreviations: BMI, body mass index; HELLP, hemolysis, elevated liver enzymes and low platelets syndrome; SD, standard deviation; TOLAC, trial of labor after cesarean
Term was defined as delivery between 37 and 41 weeks of gestation. Antepartum stillbirths, women with uterine rupture, and neonates with fetal anomalies, 5 minute Apgar score < 7, sustained a birth injury or were admitted to the neonatal intensive care unit were excluded.