Table 2.

EFM Pattern Definitions

Semi-quantitative Measures of Fetal Heart Rate Patterns in the Final 120 Minutes
Always: Present for all 120 minutes
Mostly: Present for ≥ 80 minutes
Ever: Present for ≥ 10 minutes
Total number of decelerations: the number of each type of deceleration (early, variable, late, prolonged) and their timing within the 120 minute period was extracted
Normal (Category I)
Category I EFM recordings include all of the following: Baseline rate: 110–160 beats per minute (BPM) Baseline FHR variability: moderate Late or variable decelerations: absent Early decelerations: present or absent Accelerations: present or absent
Indeterminate (Category II)
Category II EFM recordings include all not categorized as Category I or Category III. Category II EFM recordings may represent an appreciable fraction of those encountered in clinical care. Examples of Category II EFM recordings include any of the following: Bradycardia not accompanied by absent variability Tachycardia Minimal or Marked variability Absent variability not accompanied by recurrent decelerations Absence of induced accelerations after fetal stimulation Recurrent variable decelerations accompanied by minimal or moderate baseline variability Prolonged deceleration Recurrent late decelerations with moderate baseline variability Variable decelerations with other characteristics, such as slow return to baseline, “overshoots”, or “shoulders”
Abnormal (Category III)
Category III EFM recordings include either: Absent variability and any of the following: Recurrent late decelerations Recurrent variable decelerations Bradycardia Sinusoidal pattern