Table 3. Oxytocin Infusion Details by Maternal Delivery Body Mass Index (BMI) Category.
| Oxytocin Infusion Variable | Obese I (30-34.99 kg/m2) (n = 75) | Obese II (35-39.99 kg/m2) (n = 46) | Obese III (≥ 40 kg/m2) (n = 15) | p-valuea |
|---|---|---|---|---|
| Time intervals describing oxytocin infusion | ||||
| Hospital admission to oxytocin augmentation initiation (hr) | 7.49 (3.83) | 6.75 (3.53) | 6.65 (3.30) | 0.49 |
| Oxytocin augmentation initiation to vaginal delivery (hr) | 6.2 (3.87) | 6.51 (3.76) | 8.48 (4.25) | 0.13 |
| Total duration of oxytocin augmentation in labor (hr) | 4.81 (3.49) | 4.86 (3.28) | 6.22 (4.27) | 0.35 |
| Cervical dilation at time of oxytocin augmentation initiation (cm) | 6.27 (2.62) | 5.91 (2.45) | 5.00 (2.01) | 0.20 |
| Rate of oxytocin infusion | 1.49 (2.96) | 1.84 (3.97) | 2.29 (3.96) | Ob1-Ob2 p = 0.047 |
| across entire | Ob1-Ob3 p = 0.001 | |||
| augmentation (mU/min) | Ob2-Ob3 p = 0.14 | |||
| Total dose of oxytocin in labor (mU) | 1,791.67 (1,961.42) | 2,210.85 (2,668.53) | 2,757.60 (3,037.27) | 0.29 |
Note. Cells display mean (SD). Mean (SD) oxytocin rates calculated based on hourly measures during infusion (n = 1500 measurements in Obese I women, n = 920 in Obese II women, and n = 300 in Obese III women.
a
p-value for difference by BMI category calculated using one-way analysis of variance.