Fetal heart rate tracing patterns

Category I

Requires all the following criteria:

  • Baseline 110-160/min
  • Moderate variability (6-25/min)
  • No late/variable decelerations
  • ± Early decelerations
  • ± Accelerations

Category II

  • Not category I or III (indeterminate pattern)

Category III

≥1 of the following characteristics:

  • Absent variability + recurrent late decelerations
  • Absent variability + recurrent variable decelerations
  • Absent variability + bradycardia
  • Sinusoidal pattern