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Question 1

Define

Answer 1

SGA = derived from birth weight à describes a baby with AC or EFW ≤10th centile for GA

• 5% of pregnancies
• EFW = Estimated Foetal Weight; AC = Abdominal Circumference; GA = Gestational Age

· IUGR = derived from growth rate à describes a baby with a reduced growth rate à baby becomes SGA

o All IUGR babies are SGA but not all SGA babies are IUGR

Question 2

Risk factors

Answer 2

o Biggest RFs (maternal): previous stillbirth > APLS > renal disease

o Foetal – chromosomal abnormalities (à symmetrical IUGR), infection (CMV, rubella), multiple pregnancy

o Other – placental insufficiency (à asymmetrical IUGR)

Question 3

Investigations

Answer 3

(assess risk factors at booking):

1st -> if ≥1 major risk factor or ≥3 minor risk factors, reassess at 20 weeks

2nd -> at 20 weeks, if still at risk, consider…

• Minor risk (≥3 RFs) -> uterine artery doppler (20-24w) à if abnormal, serial USS from 26-28w
• Major risk (≥1 RF) à foetal size and umbilical artery doppler (serial USS from 26-28w)
• If SGA or IUGR, ultrasound biometry (biparietal diameter, head circumference, abdominal circumference and femur length) and umbilical artery doppler serial measurements (every 2 weeks) should be taken
• Screen for congenital infections

Question 4

Management

Answer 4

(n.b. no widely accepted treatments for IUGR due to uteroplacental insufficiency):

• Smoking, alcohol and drugs should be stopped
• Low-dose aspirin may have some role in preventing (not reversing) IUGR in high-risk pregnancies

Monitoring:

• 1st -> SFH or risk status determined (at booking or any antenatal appointment)
• 2nd -> confirm SGA with foetal biometry (20w)
• 3rd -> uterine artery doppler (20-24w)
• Normal -> repeat scans every 2 weeks (from 20-24w onwards)

Abnormal:
- Serial growth scans every week (from 26-28w onwards)
- Doppler ultrasound scans can be performed twice a week (umbilical artery flow)

Delivery:
- Indications for IMMEDIATE DELIVERY:
- Abnormal CTG (and reduced foetal movements)

Reversal of end-diastolic flow
- Delivery by 37 weeks is usually necessary à dependent on severity and gestation
- Steroids should be given <36 weeks
- Consultant-led clinics and decision-making

Question 5

Conclusions

Answer 5

Stillbirth PTL Intrapartum foetal distress

• Birth asphyxia
• Meconium aspiration
• Postnatal hypoglycaemia
• Neurodevelopmental delay
• Risk T2DM and HTN in adult life

Prognosis -> increased perinatal morbidity and mortality, increased neurodevelopmental delay if onset <26/40