"VEAL CHOP" FHR PATTERN

SWARAJ HOSPITAL & RESEARCH INSTITUTE

BOLANGIR, ODISHA  •  OBSTETRICS & GYNAECOLOGY CLINICAL PATHWAY SERIES

Clinician Reference Infographic

Fetal Heart Rate Patterns — A Visual Reference

Recognizing a fetal heart rate pattern by its shape on the trace is the foundation of CTG interpretation. This quick-reference lines up baseline patterns, variability, and the periodic patterns side by side so their shapes can be told apart at a glance. For what to actually do about each pattern, see our companion "Fetal Heart Rate Monitoring" guide.

📏 BASELINE RATE — WHERE THE LINE SITS

Normal

110–160 bpm

Reassuring

Tachycardia

> 160 bpm

Non-reassuring

Bradycardia

< 110 bpm

Non-reassuring

The shaded band marks the normal range — a trace sitting consistently above or below it is what defines tachycardia or bradycardia, not a brief blip.

Tachycardia — common causes: maternal fever or chorioamnionitis, fetal hypoxia, prematurity, certain drugs (e.g., beta-sympathomimetics), fetal tachyarrhythmia

Bradycardia — common causes: prolonged cord compression, maternal hypotension, uterine hyperstimulation, or an acute hypoxic event — prolonged bradycardia is an emergency

📶 VARIABILITY — THE AMPLITUDE SPECTRUM

Absent

< 2 bpm

Abnormal

Minimal

2–5 bpm

Non-reassuring

Moderate

5–25 bpm

Reassuring

Marked

> 25 bpm

Uncertain

Sinusoidal

Smooth wave

Ominous

🌊 PERIODIC & EPISODIC PATTERNS

AccelerationReassuring

Shape: abrupt rise, ≥15 bpm for ≥15 sec. Not tied to contractions.
Likely cause: fetal movement or stimulation — a sign of an active, well-oxygenated fetus.

Early DecelerationBenign

Timing: mirrors the contraction exactly — nadir lines up with the peak.
Likely cause: fetal head compression as it descends — a normal, expected finding in active labor.

Variable DecelerationDepends

Shape: abrupt, jagged drop — variable in timing and shape from one to the next.
Likely cause: umbilical cord compression — common, but repeated deep or slow-to-recover ones need closer attention.

Late DecelerationConcerning

Timing: gradual dip that lags behind the contraction — nadir occurs after the peak.
Likely cause: uteroplacental insufficiency — the placenta struggling to keep up with contractions; repetitive late decelerations need prompt action.

Prolonged DecelerationConcerning

Duration: lasts > 3 minutes (bradycardia if > 10 minutes) — spans multiple contractions rather than resolving with one.
Likely cause: often an acute event — cord prolapse, uterine rupture, abruption, hyperstimulation, or maternal hypotension. Needs immediate assessment every time.

Timing tells the story: early mirrors the contraction, late lags behind it, and variable doesn't follow any consistent pattern at all.

〰️ UTERINE CONTRACTIONS — THE REFERENCE SIGNAL

The orange trace in every tile above is the tocograph — contractions are the timeline that gives decelerations their meaning

Normal

3–5 in 10 min, 45–80 sec each

Expected

Tachysystole

> 5 in 10 min

Reduce/stop stimulant

Tachysystole most often occurs during induction or augmentation with oxytocin or prostaglandins — see our companion Induction & Augmentation of Labor guide for how to respond.

🗓️ THESE PATTERNS APPLY ANTENATALLY TOO

The non-stress test (NST) uses the same baseline, variability, and acceleration features — but outside labor, and without contractions to reference

Reactive NST: two or more accelerations within a 20-minute window — reassuring

Non-reactive NST: fails to meet that criterion after an extended period — needs further evaluation (e.g., vibroacoustic stimulation, biophysical profile, or Doppler studies)

⚠️ SINUSOIDAL PATTERN — RARE BUT OMINOUS

A smooth, regular, sine-wave-like oscillation — quite different from the irregular jaggedness of normal variability

Classically associated with severe fetal anaemia — including from Rh isoimmunization, fetomaternal haemorrhage, or twin anaemia-polycythaemia sequence

Rare, but treat as an abnormal pattern requiring urgent senior review every time it's seen

Memory Aid

VEAL CHOP

A classic way to link each periodic pattern to its likely cause — useful for a quick mental check while reading a trace.

V

Variable decelerations → Cord compression

E

Early decelerations → Head compression

A

Accelerations → Okay — reassuring fetal status

L

Late decelerations → Placental insufficiency

Reminder: a mnemonic is a starting point for recall, not a substitute for systematic interpretation — always assess the whole trace in clinical context.

Swaraj Hospital & Research Institute · Department of Obstetrics & Gynaecology, Bolangir, Odisha

Clinician-facing visual reference for structured teaching; waveforms are illustrative approximations for pattern recognition, not tracings from real cases. Classification and escalation follow local labour ward protocol.