How many days should Cardiotocography (CTG) monitoring be done in a baby with Intrauterine Growth Restriction (IUGR), is it 3 days?

Cardiotocography (CTG) Monitoring in IUGR Babies

For babies with Intrauterine Growth Restriction (IUGR), cardiotocography (CTG) monitoring should be performed at least twice weekly, with increased frequency to 2-3 times per week when IUGR is complicated by absent or reversed end-diastolic flow in the umbilical artery. 1, 2

Monitoring Frequency Based on IUGR Severity

The frequency of CTG monitoring depends on the severity of IUGR and umbilical artery Doppler findings:

Normal Umbilical Artery Doppler

• Weekly CTG monitoring after fetal viability 2
• Twice weekly nonstress testing with weekly amniotic fluid evaluation 1
• Consider delivery at 38-39 weeks 1

Decreased End-Diastolic Flow

• Increase frequency of testing 1
• Consider delivery at >37 weeks 1

Absent End-Diastolic Flow (AEDV)

• CTG monitoring 2-3 times per week 1, 2
• Consider delivery at >34 weeks 1

Reversed End-Diastolic Flow (REDV)

• Daily CTG monitoring (1-2 times per day) 2
• Hospitalization recommended 2
• Consider delivery at >32 weeks 1

Additional Considerations

• Hospitalization may be offered when fetal testing more than 3 times per week is deemed necessary 1
• The combination of ultrasound and cardiotographic surveillance techniques has been shown to improve outcomes for IUGR fetuses 1
• For very early gestational age IUGR (e.g., at 25 weeks) with absent or reversed end-diastolic flow, aggressive interventions may be deferred given the poor prognosis 1

Important Monitoring Nuances

• Early-onset IUGR (<32 weeks) differs from late-onset IUGR (≥32 weeks) in monitoring approach 3:

  • Early-onset: Focus on venous Doppler parameters and computerized CTG
  • Late-onset: Focus on cerebral Doppler parameters

• Computerized CTG (cCTG) is particularly useful for evaluating chronic hypoxemia in IUGR fetuses 4

• Parameters that help distinguish between IUGR and healthy fetuses before 36 weeks include fetal heart rate baseline, short-term variability, long-term irregularity, and delta 4

Clinical Pitfalls to Avoid

• Don't rely solely on CTG monitoring; integrate with fetal ultrasound and Doppler vessel evaluation to better predict neonatal outcomes 4
• Don't use the same monitoring protocol for early-onset and late-onset IUGR as they have different pathophysiology and progression patterns 3
• Don't delay corticosteroid administration when indicated (absent or reversed end-diastolic flow at <34 weeks), but ensure close observation for 48-72 hours afterward due to potential increased physiologic demands 1

Remember that the goal of monitoring is to balance the risks of prematurity against the risks of continued intrauterine stay in a compromised environment, with the ultimate aim of reducing perinatal morbidity and mortality.