In a 35‑week pregnant woman with maternal hypertension and fetal intra‑uterine growth restriction who now has an elevated umbilical‑artery Doppler (high resistance), what is the appropriate management?

Management of Elevated Umbilical Artery Doppler in IUGR at 35 Weeks with Maternal Hypertension

In this 35-week pregnancy with maternal hypertension, IUGR, and elevated umbilical artery Doppler resistance, you should immediately intensify fetal surveillance to weekly umbilical artery Doppler studies, initiate twice-weekly cardiotocography, and plan delivery at 37 weeks if end-diastolic flow remains present—or earlier if absent/reversed end-diastolic flow develops. 1, 2

Immediate Assessment Required

Determine the specific Doppler abnormality pattern now, as this dictates all subsequent management decisions:

• Elevated resistance indices (>95th percentile) with preserved end-diastolic flow: Indicates early placental dysfunction requiring weekly surveillance 1, 2
• Absent end-diastolic velocity (AEDV): Signifies ~70% obliteration of placental vessels and mandates delivery planning at 34 weeks 1, 2
• Reversed end-diastolic velocity (REDV): Represents advanced placental compromise requiring delivery consideration at 32 weeks 1, 2

The distinction between these patterns is critical because AEDV and REDV carry dramatically higher stillbirth risk compared to elevated resistance alone 1

Surveillance Protocol Based on Doppler Findings

If Elevated Resistance with Preserved End-Diastolic Flow:

• Weekly umbilical artery Doppler studies to detect progression to AEDV 1, 2
• Twice-weekly nonstress testing with weekly amniotic fluid assessment, or weekly biophysical profile testing 1
• Fetal biometry every 2 weeks to monitor growth trajectory 1
• Plan delivery at 37 weeks given the combination of maternal hypertension and IUGR 1, 2

If Absent End-Diastolic Flow Develops:

• Increase Doppler surveillance to 2-3 times per week due to risk of rapid deterioration to reversed flow 1, 2
• Daily cardiotocography monitoring 1
• Administer antenatal corticosteroids immediately if not already given 1, 2
• Deliver at 33-34 weeks after corticosteroid administration 1, 2
• Strongly consider cesarean delivery due to high risk of intrapartum fetal compromise 2

If Reversed End-Diastolic Flow Develops:

• Hospitalize immediately 1
• Daily cardiotocography with 3× weekly Doppler assessment 1
• Deliver at 30-32 weeks after corticosteroid administration 1, 2
• Cesarean delivery is indicated given severe placental insufficiency 2

Essential Antenatal Interventions

Corticosteroids for fetal lung maturation: Administer betamethasone 12 mg IM × 2 doses (24 hours apart) if AEDV or REDV develops and gestational age is <34 weeks 1, 2

Magnesium sulfate for neuroprotection: Give 4-6 g IV loading dose followed by 1-2 g/h infusion if delivery is anticipated before 32 weeks 1, 2

Mode of Delivery Considerations

Cesarean delivery should be strongly considered if AEDV or REDV is present, as these fetuses have 75-95% risk of requiring cesarean for intrapartum fetal heart rate abnormalities 2, 3

Induction of labor may be reasonable only when resistance indices are elevated but end-diastolic flow remains present, with mandatory continuous fetal monitoring throughout labor 2

Critical Pitfalls to Avoid

Do not rely on intermittently elevated Doppler values alone: If the umbilical artery Doppler fluctuates between normal and elevated, manage as if persistently elevated when IUGR is confirmed, though perinatal outcomes may be similar to normal Doppler 4

Do not delay delivery for repeat testing if AEDV or REDV is documented at ≥34 weeks or ≥32 weeks respectively, as the risk of stillbirth increases dramatically with venous Doppler abnormalities 1

Recognize the gestational age-dependent progression: Early-onset severe placental dysfunction (diagnosed <27 weeks) progresses rapidly (7-day intervals), while later-onset mild dysfunction may take 33 days to progress, but at 35 weeks you are already in a window requiring active management 5

Assess for preeclampsia progression: The combination of maternal hypertension and IUGR with abnormal Doppler increases risk of placental inflammation and chronic villitis, which may necessitate earlier delivery if maternal condition deteriorates 6