Obgyn · Year 3 · from Obgyn

Case 3: Intrauterine Growth Restriction with Abnormal Dopplers

Patient Demographics

  • Age: 33 years
  • Sex: Female
  • Occupation: Accountant

Chief Complaint

"My doctor said the baby is too small and the blood flow is abnormal."

History of Present Illness

The patient is G1P0 at 28 weeks gestation. She was noted to have a fundal height measuring 3 cm below expected for dates. Growth ultrasound revealed estimated fetal weight below the 5th percentile. She was referred for maternal-fetal medicine consultation and Doppler evaluation. She feels fetal movement daily. She denies vaginal bleeding, leakage of fluid, or contractions.

Past Medical History

  • Chronic hypertension diagnosed 2 years ago, on labetalol
  • No diabetes

Prenatal Course

  • Chronic hypertension controlled on labetalol 200 mg twice daily
  • BP range 120-135/75-85 throughout pregnancy
  • No proteinuria to date
  • Anatomy ultrasound at 20 weeks was normal

Physical Examination Findings

  • Vital Signs: BP 138/88 mmHg, HR 72 bpm
  • Abdomen: Fundal height 25 cm (3 cm below expected 28 cm)
  • Lower extremities: Trace edema bilaterally

Diagnostic Workup

Growth Ultrasound:

  • EFW 780 grams (<3rd percentile for 28 weeks)
  • Abdominal circumference <3rd percentile
  • Head circumference 15th percentile
  • Femur length 12th percentile
  • Pattern: Asymmetric IUGR (head-sparing) - suggests placental insufficiency
  • AFI 6 cm (low-normal)

Umbilical Artery Doppler:

  • Elevated systolic/diastolic ratio (>95th percentile)
  • End-diastolic flow PRESENT but reduced
  • Interpretation: Increased placental vascular resistance

Middle Cerebral Artery Doppler:

  • Pulsatility index decreased (<5th percentile)
  • Interpretation: Cerebral redistribution (brain-sparing)

Ductus Venosus Doppler:

  • A-wave present (forward flow during atrial contraction)
  • Currently normal

Diagnosis

Severe Early-Onset Intrauterine Growth Restriction

  • EFW <3rd percentile at 28 weeks
  • Asymmetric pattern (placental insufficiency)
  • Abnormal umbilical artery Doppler (elevated resistance)
  • Evidence of fetal compensation (brain-sparing on MCA)
  • Associated with chronic hypertension

Risk Assessment

  • High risk for adverse outcomes
  • Currently compensated (positive end-diastolic flow, normal ductus venosus)
  • Risk of progression to absent/reversed end-diastolic flow

Management Plan

Antenatal Corticosteroids:

  • Betamethasone 12 mg IM x 2 doses given (for potential preterm delivery)

Fetal Surveillance (Intensive Protocol):

  • Twice-weekly NST and biophysical profile
  • Umbilical artery Doppler twice weekly
  • If absent end-diastolic flow develops: daily Doppler, consider delivery
  • If reversed end-diastolic flow: delivery recommended at viable gestational age

Maternal Monitoring:

  • Blood pressure monitoring for superimposed preeclampsia
  • Weekly labs: CBC, CMP, LFTs, uric acid
  • 24-hour urine protein (baseline for preeclampsia surveillance)

Delivery Timing:

  • Current status (abnormal UA Doppler with present end-diastolic flow): aim for 34-37 weeks
  • If absent end-diastolic flow develops: 32-34 weeks
  • If reversed end-diastolic flow: 30-32 weeks with ductus venosus assessment
  • If abnormal ductus venosus or BPP <6: delivery regardless of gestational age

Hospital Course

Weeks 28-30:

  • Twice-weekly testing with NSTs reactive
  • Umbilical artery Doppler persistently abnormal but end-diastolic flow present
  • EFW at 30 weeks: 950 grams (<3rd percentile, minimal interval growth)

Week 31:

  • Developed absent end-diastolic flow on umbilical artery Doppler
  • Admitted for daily monitoring
  • Ductus venosus remained normal
  • Magnesium sulfate for neuroprotection initiated

Delivery at 32 weeks 1 day:

  • Indication: Persistent absent end-diastolic flow with declining biophysical profile (6/10)
  • Cesarean delivery (failed induction at this gestational age, IUGR)
  • Male infant: 1,020 grams, Apgar 6/8
  • Admitted to NICU: required initial respiratory support, otherwise stable

Clinical Image

Image Description: Umbilical artery Doppler waveforms comparing normal flow pattern (with positive end-diastolic flow), elevated S/D ratio, absent end-diastolic velocity (AEDV), and reversed end-diastolic velocity (REDV). These patterns indicate progressive placental vascular resistance.

Attribution: Image from Radiopaedia. Educational case. Licensed under CC BY-NC-SA 3.0. Source: https://radiopaedia.org/articles/umbilical-artery-doppler

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