How should a 36-year-old G3P1 woman at 37 weeks 2 days gestation with a non-engaged cephalic/breech presentation, borderline hypotension, mild tachycardia, inadequate gestational weight gain, and a history of threatened abortion and dilation-and-curettage be managed?

Management of G3P1 at 37 Weeks with Constitutionally Small Fetus and Non-Engaged Cephalic Presentation

This patient should be delivered at 37 weeks gestation given the diagnosis of fetal growth restriction (FGR) with estimated fetal weight below the 17th percentile at 32 weeks, regardless of umbilical artery Doppler findings. 1

Immediate Assessment Required

Fetal Surveillance

• Perform umbilical artery Doppler assessment immediately to stratify delivery timing and risk 1

  • If Doppler shows decreased diastolic flow (S/D, RI, or PI >95th percentile) without absent/reversed end-diastolic velocity (AEDV/REDV): deliver at 37 weeks 1
  • If severe FGR with estimated fetal weight <3rd percentile: deliver at 37 weeks 1
  • If umbilical artery Doppler is normal and EFW between 3rd-10th percentile: deliver at 38-39 weeks 1
  • If AEDV detected: deliver at 33-34 weeks (already past this window) 1
  • If REDV detected: deliver at 30-32 weeks (already past this window) 1

• Perform cardiotocography (CTG) testing to assess fetal well-being 1

  • Non-reassuring fetal status is an indication for immediate delivery 2

• Assess amniotic fluid volume via single deepest vertical pocket 1

  • Oligohydramnios (<2 cm) with FGR warrants delivery at 34-37 weeks 1

Maternal Assessment

• Blood pressure monitoring is critical given borderline hypotension (90/60 mmHg) and mild tachycardia (108 bpm) 2, 3

  • While this patient does not meet criteria for hypertensive disorders, the low BP requires monitoring for dehydration or other causes 3
  • Repeat vital signs every 15-30 minutes if symptomatic 3
  • Ensure adequate hydration given inadequate gestational weight gain (8 kg vs recommended 12.5-18 kg) 4

• Rule out preeclampsia despite normal BP, given FGR and history of threatened abortion 2

  • Check urine protein/creatinine ratio 2
  • Obtain CBC, platelet count, liver transaminases, creatinine, uric acid 2
  • These labs should be performed at least twice weekly if preeclampsia suspected 2

Delivery Planning

Timing of Delivery

Deliver at 37 weeks 2 days (current gestational age) to 37 weeks 6 days maximum 1

• The Society for Maternal-Fetal Medicine recommends delivery at 37 weeks for FGR with decreased diastolic flow or severe FGR with EFW <3rd percentile 1
• Do not delay beyond 37+6 weeks for fetuses with birthweight below 3rd centile due to highest stillbirth risk 5

Mode of Delivery Considerations

• Cephalic presentation that is not engaged does not automatically require cesarean delivery 1

  • The non-engaged status at 37 weeks is not uncommon, particularly in multiparous women 6
  • Growth-restricted fetuses have increased risk of intrapartum fetal heart rate decelerations and emergency cesarean 1
  • Plan for continuous electronic fetal monitoring during labor 1
  • Have immediate access to operating room for emergency cesarean if non-reassuring fetal status develops 1

• Consider cesarean delivery if 1:

  • AEDV or REDV present on umbilical artery Doppler 1
  • Non-reassuring fetal status on CTG 1, 2
  • Failed induction or labor dystocia 1

External Cephalic Version (ECV) Consideration

ECV is NOT indicated in this case 6, 7, 8

• ECV is typically performed at 36-37 weeks for breech presentation 8, 9
• This fetus is cephalic (not breech), though not engaged 6
• The Leopold maneuvers description is somewhat confusing (mentions "breech elements" but states cephalic presenting part), requiring immediate ultrasound confirmation of fetal presentation 6
• If truly breech: ECV success rates are lower with FGR and may not be appropriate given need for delivery at 37 weeks 7, 10, 9

Ongoing Management Until Delivery

Nutritional Support

• Continue ferrous sulfate with folic acid and multivitamins (current regimen is appropriate) 1
• Increase caloric intake to address inadequate gestational weight gain 4, 11
  • Current 8 kg gain is below recommended 12.5-18 kg for pre-pregnancy underweight BMI 4
  • Inadequate GWG associated with FGR and adverse outcomes 4, 11

Fetal Monitoring Schedule

• Weekly umbilical artery Doppler if decreased diastolic flow or severe FGR 1
• Weekly CTG testing until delivery 1
• Increase CTG frequency to 1-2 times daily if AEDV/REDV detected 1

Maternal Monitoring

• Monitor blood pressure given borderline hypotension 2, 3
• Assess for symptoms of preeclampsia: headache, visual changes, epigastric pain, edema 2
• Monitor fetal movement daily; decreased movement warrants immediate evaluation 5

Common Pitfalls to Avoid

1. Do not delay delivery beyond 37 weeks in FGR, even with normal Doppler 1, 5
2. Do not assume vaginal delivery is contraindicated based solely on non-engaged presentation 1
3. Do not overlook maternal hypotension as a potential sign of dehydration or other pathology 3
4. Do not use uric acid or proteinuria levels alone as delivery indications 2
5. Confirm fetal presentation with ultrasound given ambiguous Leopold findings 6

Antenatal Corticosteroids

Not indicated at 37 weeks gestation 1

• Corticosteroids recommended only if delivery anticipated before 33 6/7 weeks or between 34 0/7-36 6/7 weeks 1

Magnesium Sulfate for Neuroprotection

Not indicated at 37 weeks gestation 1

• Magnesium sulfate for fetal neuroprotection recommended only for pregnancies <32 weeks 1
• Would be indicated for eclampsia prophylaxis if preeclampsia with severe features develops 2