Fetal growth restriction and small for gestational age — structured SAQ (15 marks)

(a) Classification (3 marks)

One mark for the diagnosis, one for the solitary parameter, one for naming the consensus. ^[1]

• This is early fetal growth restriction (under 32 weeks), defined by the Gordijn 2016 Delphi consensus. The EFW and AC under the 3rd centile are solitary parameters — each is sufficient alone to diagnose FGR.^[1]
• The raised UA-PI above the 95th centile is a contributory parameter that further supports the diagnosis and indicates placental insufficiency as the cause.^[1]
• It is not 'small for gestational age' (a size label); it is FGR (a pathology), because the Doppler confirms failed placentation.^[1]

(b) Surveillance plan (4 marks)

One mark for naming Doppler as the cornerstone, one for the modalities, one for the interval, one for the principle. ^[1][4]

• Umbilical artery Doppler is the surveillance cornerstone, with the Alfirevic Cochrane review confirming it reduces perinatal death (RR 0.71) in high-risk pregnancy — not CTG alone.^[4]
• Modalities: biometry (EFW, AC) every 2 to 4 weeks for growth velocity; umbilical artery Doppler at each visit; cerebroplacental ratio and middle cerebral artery; amniotic fluid volume; and, in early severe FGR, ductus venosus and computerised CTG.^[1]
• Interval: at this Doppler severity (raised PI, EFW under 3rd centile), surveillance at least every 2 weeks, and sooner if there is any change in the Doppler.^[1]
• Principle: a normal Doppler today does not exclude deterioration before the next scan — the interval is part of the prescription.^[4]

(c) The role of TRUFFLE in delivery timing (4 marks)

One mark for naming the trial, one for the surveillance sequence, one for the delivery triggers, one for the outcome. ^[2][3]

• TRUFFLE (Trial of Randomised Umbilical and Fetal Flow in Europe) is the trial that informs delivery timing in early-onset FGR. It recruited women at 26 to 32 weeks with AC under the 10th centile and UA-PI above the 95th, randomised to delivery triggered by early or late computerised CTG changes, or by abnormal ductus venosus.^[2]
• The surveillance sequence in early FGR is: raised UA-PI, then low CPR (brain-sparing), then abnormal ductus venosus, then abnormal CTG.^[2]
• Delivery is triggered by abnormal ductus venosus waveform or computerised fetal heart rate analysis, balancing gestational age against fetal compromise; if Dopplers remain stable, delivery around 37 weeks.^[2]
• The 2-year neurodevelopmental outcomes were best in the groups delivered for ductus venosus or computerised CTG indicators, supporting the use of these late markers as triggers rather than a short-term CTG alone.^[3]

(d) Absent end-diastolic flow at 31 weeks (4 marks)

One mark for the significance, one for admission, one for corticosteroids and neonatology, one for delivery timing. ^[2]

• Absent end-diastolic flow is a high-risk finding — it indicates severe placental resistance with a sharply rising risk of stillbirth and fetal acidosis.^[2]
• Admit for inpatient surveillance with regular Doppler (including ductus venosus), computerised CTG, and daily fetal monitoring.^[2]
• Give antenatal corticosteroids for fetal lung maturity (delivery is likely before 34 weeks), and involve neonatology for anticipated preterm and growth-restricted infant care.^[2]
• Delivery timing: plan delivery around 32 to 34 weeks (or earlier if the ductus venosus or computerised CTG become abnormal), usually by caesarean because the growth-restricted fetus tolerates labour poorly. Counsel the woman honestly about the realistic outcomes of early severe FGR.^[2][3]