What is the best course of action for a pregnant woman at 35 weeks of gestation with significant fetal growth restriction and absent end-diastolic flow on umbilical artery Doppler (ultrasound)?

Management of FGR with Absent End-Diastolic Flow at 35 Weeks

This patient requires delivery at 33-34 weeks of gestation, and since she is already at 35 weeks, delivery should be expedited now. 1, 2, 3

Immediate Management Steps

Delivery Timing

• The Society for Maternal-Fetal Medicine (SMFM) explicitly recommends delivery at 33-34 weeks of gestation for pregnancies with FGR and absent end-diastolic velocity (AEDV). 1 At 35 weeks, this patient has already exceeded the recommended delivery window.

• The rationale is that neonatal morbidity and mortality rates associated with AEDV exceed the complications of prematurity at 33-34 weeks gestational age. 3

• Delaying delivery beyond this window increases the risk of stillbirth and severe perinatal morbidity without providing meaningful benefit from additional fetal maturation. 1, 2

Route of Delivery

• Cesarean delivery should be strongly considered based on the clinical scenario for pregnancies with FGR complicated by AEDV. 1, 3

• FGR fetuses with AEDV have a 75-95% rate of intrapartum fetal heart rate decelerations requiring emergency cesarean delivery. 3

• Studies demonstrate that cesarean delivery is associated with lower perinatal mortality compared to vaginal delivery in the setting of AEDV, with one study showing perinatal mortality twice as high with vaginal birth. 4

• While SMFM states cesarean should be "considered based on the entire clinical scenario," the high rates of intrapartum complications and the severe growth restriction (fundal height 6 weeks behind) favor immediate cesarean section (Option B) in this case. 1, 3, 4

Why Other Options Are Incorrect

Option A (Induce Labor)

• Labor induction carries substantial risk given the 75-95% likelihood of requiring emergency cesarean for fetal heart rate abnormalities during labor. 3
• The severe placental insufficiency indicated by AEDV makes the fetus poorly equipped to tolerate labor contractions. 4, 5

Option C (Forget)

• This is clearly inappropriate as AEDV represents severe placental compromise with high risk of fetal demise if delivery is delayed. 5, 6
• Historical data shows 8 of 9 fetuses with absent or reversed end-diastolic flow resulted in intrauterine or neonatal death without timely intervention. 5

Option D (Repeat Doppler in 1 Week)

• Once AEDV is confirmed, the recommendation is for delivery at 33-34 weeks, not continued surveillance. 1
• Waiting one week would place the patient at 36 weeks, well beyond the recommended delivery window and unnecessarily increasing fetal risk. 2, 3
• AEDV warrants Doppler assessment 2-3 times per week if delivery is being delayed for specific reasons (such as steroid administration), not weekly reassessment. 1, 2

Pre-Delivery Interventions

Corticosteroids

• Since the patient is at 35 weeks (between 34 0/7 and 36 6/7 weeks), antenatal corticosteroids should be administered if she has not received a prior course and delivery is anticipated within 7 days. 1, 2, 3

Magnesium Sulfate

• Magnesium sulfate for neuroprotection is recommended for pregnancies less than 32 weeks, so it is not indicated at 35 weeks. 1, 2, 3

Clinical Context

The significant discordance between fundal height (29 weeks) and gestational age (35 weeks) indicates severe FGR, likely with estimated fetal weight well below the 10th percentile. 1 Combined with AEDV, this represents advanced placental compromise with obliteration of approximately 70% of placental tertiary villi arteries. 1

The answer is B: Immediate delivery by caesarean section.