Small for dates

Question 1

What is IUGR?

Answer 1

Slowing of fetal growth such that it fails to reach growth potential.

Question 2

What is the aetiology of IUGR?

Answer 2

Maternal: HTN, PREC, DM, DU, smoking, CKD, thrombophilia, maternal age high.

Fetal: chromosomal abnormalities, infection (CMV/Rubella) multiple pregnanct

Other: placental insufficiency.

Question 3

What are the RFs of IUGR?

Answer 3

As for aetiology, Hx of IUGR.

Question 4

What is the epidemiology of IUGR?

Answer 4

3-5% of pregnancies.

Question 5

What is the Hx/Exam of IUGR?

Answer 5

Any of the aetiological factors noted above, enquire on fetal movements.

Abdomen: low fundal height.

Question 6

What pathology is IUGR?

Answer 6

Symmetrical IUGR: head and body proportionately small, normally early onset, seenin chromosomal anomalies.

Asymmetrical IUGR: later onset, abdominal circumference disproportionately smaller than head, seen with placental insufficiency.

Question 7

What Ix would you do for IUGR?

Answer 7

USS: anomaly scan, growth (abdominal and head circumference), loquor volume (OGHMN?) umbilical doppler (abnormal if end diastolic flow absent or reversed). MCA doppler (redistribution of blood to brain).

CTG: fetal wellbeing.

Question 8

What is the Mx of IUGR?

Answer 8

Normal doppler resultsL aim for delivery at >37wk, unless anomalies arise. Regular monitoring.

Abnormal doppler: Steroids if pre term, consider delivery, paediatrician at delivery, continuous CTG intrapartum.

Question 9

What are the complications/ prognosis of IUGR?

Answer 9

Tillbirth, PTL, intrapartum fetal distress, asphyxia, meconium aspiration, postnatal hypoglycaemia, neurodevelopmental delay, high risk of t2DM in life.

Increased perinatal morbidity and mortality, increased neurodevelopmental delay if onset <26/40.

Question 10

What is small for gestational age?

Answer 10

derived from birth weight -> describes a baby with AC or EFW ≤10th centile for GA
o 5% of pregnancies
o EFW = Estimated Foetal Weight; AC = Abdominal Circumference; GA = Gestational Age

Question 11

What are RFs for SGA?

Answer 11

o Biggest RFs (maternal): previous stillbirth > APLS > renal disease
o Foetal – chromosomal abnormalities (-> symmetrical IUGR), infection (CMV, rubella), multiple pregnancy
o Other – placental insufficiency (-> asymmetrical IUGR)

Question 12

What Ix do you do for SGA?

Answer 12

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

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

• > Minor risk (≥3 RFs) -> uterine artery doppler (20-24w) -> if abnormal, serial USS from 26-28w
• > Major risk (≥1 RF) -> foetal size and umbilical artery doppler (serial USS from 26-28w)

o 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

o Screen for congenital infections

Question 13

What is the management for SGA?

Answer 13

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

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

o Delivery:
 Indications for IMMEDIATE DELIVERY:
• Abnormal CTG (and reduced foetal movements)
• Reversal of end-diastolic flow
 Delivery by 37 weeks is usually necessary -> dependent on severity and gestation
• Steroids should be given <36 weeks
• Consultant-led clinics and decision-making