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A study of variable decelerations in association with other heart rate patterns during monitored labor
A review of 1,011 consecutive intrapartum heart rate tracings yielded 37.3% with some degree of variable deceleration pattern. No differences in Apgar score distribution were observed in the presence of uncomplicated variable deceleration pattern when compared to those tracings marked normal. However, the presence of variable decelerations in association with other heart rate patterns resulted in lower mean Apgar scores at 1 and 5 minutes, which were significantly different from those of the fetal heart rate (FHR) normal group. Mean Apgar scores at 1 and 5 minutes were significantly different from normal when variable decelerations were noted in the presence of tachycardia and loss of variability. Mean Apgar scores were lower when bradycardia (prolonged episodes of heart rate less than 120 bpm) was present in the record when compared to normal, but the presence of variable decelerations with bradycardia did not result in different mean scores. The presence of baseline changes with loss of variability and variable decelerations appeared to result in the lowest mean scores. When bradycardia or tachycardia occurred in exclusive association with variable decelerations, the percentage of depressed newborn infants was relatively high.
A review of 1,011 consecutive intrapartum heart rate tracings yielded 37.3% with some degree of variable deceleration pattern. No differences in Apgar score distribution were observed in the presence of uncomplicated variable deceleration pattern when compared to those tracings marked normal. However, the presence of variable decelerations in association with other heart rate patterns resulted in lower mean Apgar scores at 1 and 5 minutes, which were significantly different from those of the fetal heart rate (FHR) normal group. Mean Apgar scores at 1 and 5 minutes were significantly different from normal when variable decelerations were noted in the presence of tachycardia and loss of variability. Mean Apgar scores were lower when bradycardia (prolonged episodes of heart rate less than 120 bpm) was present in the record when compared to normal, but the presence of variable decelerations with bradycardia did not result in different mean scores. The presence of baseline changes with loss of variability and variable decelerations appeared to result in the lowest mean scores. When bradycardia or tachycardia occurred in exclusive association with variable decelerations, the percentage of depressed newborn infants was relatively high.
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