| Abstract
Objectives: Cardiotocography (CTG) is a tool for assessing the fetus during labor and identifying the risk of asphyxia. Abnormal
CTG can lead to stress in the physician and mother and result in their decision in terminating the pregnancy and the complications
of an emergency cesarean section. The purpose of this study was the evaluation of the correlation between nonreassuring patterns
in fetal CTG and birth asphyxia.
Materials and Methods: In a cross-sectional analytic study, 324 term pregnant women were included. The association between
nonreassuring patterns in CTG (fetal tachycardia, fetal bradycardia, absent or minimal baseline variability, and absence of acceleration
and periodic or episodic deceleration) and birth asphyxia were assessed.
Results: Birth asphyxia existed in 10 newborns; in all cases mild hypoxic ischemic encephalopathy (HIE) was observed. Within
the nonreassuring CTG patterns, baseline fetal heart variability and periodic or episodic deceleration had a significant relationship
with birth asphyxia. Most asphyxia cases had occurred in absent and minimal baseline fetal heart rate (FHR) variability (R=0.49,
P<.001). In periodic or episodic decelerations, most asphyxia cases occurred in recurrent late decelerations with normal baseline
variability and variable decelerations with shoulders or overshoots (R=0.42, P=.014).
Conclusion: With regard to the findings of the present study we can use nonreassuring cardiotocographic patterns, especially absent
and minimal baseline FHR variability and periodic or episodic decelerations in prediction of birth asphyxia. It seems however that
most birth asphyxias occur in normal cardiotocographs. |