A comparison of fetal outcome in birth chair and delivery table births.

This study was conducted to determine the effect of the birth chair on fetal outcome in primigravid subjects with a normal pregnancy and labor. A quasi-experimental design was used to compare 33 birth-chair deliveries with 22 delivery-table deliveries. No difference between groups was found in the mean pH and pO2 of arterial and venous cord blood samples. The mean arterial pCO2 was lower in the chair group (49.25 and 44.50, p = 0.023), but there was no difference in venous pCO2. In the chair group, the mean vein pO2 was higher when the angle of the chair was more than 45 degrees upright (22.3 and 28.4, p = 0.007). Means for chair and table groups were similar for maternal hemoglobin, breathholding while pushing, duration of second stage, time of first cry, time of cord clamping, and Apgar scores. Incidence of cord around the neck was identical. The mean one-minute Apgar scores were significantly higher when chair or table was more than 30 degrees upright (8.0 and 8.59, p = 0.037). Results suggest that the birth chair is a safe alternative to the delivery table in terms of fetal outcome. The findings of lower arterial pCO2 with unchanged pO2 and pH in the chair group, support earlier findings of less transient cord compression in upright positions.