Small for Gestational Age

Question 1

What is the definition of small for gestational age?

Answer 1

Estimated foetal weight EFW<10th centile
Severe is EFW<3 centile

Question 2

How is foetal size measured?

Answer 2

foetal size is measured via:
1. Symphyseal fundal height(top of utereus to pelvic bone)
2. Foetal abdominal circumference
3. Femur length
4. Head circumference
5. Liquor volume/amniotic fluid index

Question 3

RF for Small for Gestational Age

Answer 3

● Major - odds ratio >2.0 for SGA:
1. Maternal age >40
2. Smoker >11 cigarettes per day.
3. Maternal cocaine use in pregnancy.
4. Maternal daily vigorous exercise
5. Previous SGA baby
6. Previous stillbirth
7. Maternal SGA
8. Paternal SGA
9. Chronic hypertension
10. Diabetes with vascular disease
11. Renal impairment
12. Antiphospholipid syndrome
● Minor risk factors include nulliparity and previous pre-eclampsia.
● Further major risk factors that may arise during pregnancy include pre-eclampsia,
unexplained APH and low maternal weight gain.

Question 4

How is SGA IVx

Answer 4

1st - Symphyseal fundal height sfh
SFH plotted on growth chart (modiified to maternal details)
2nd. USS scan

IF major risk factor/confirmed :
Serial (2 weekly) USS and umbilical artery Doppler from 26-28 weeks

Question 5

What can an umbilical artery ultrasound tell about SGA - small for gestational age

Answer 5

Normal low resistance placenta allows continous flow from foetus to placenta thoughout the cardiac cycle (systole & diastole)
if end diastolic flow is slow/reversed -

This suggest increased placental resistance = placental compromise

This is PREDICTIVE OF SGA.

Question 6

SGA TX

Answer 6

C section