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Flashcards in FGR/SGA Deck (15)
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1

Definition

• Fetal Growth Restriction (FGR) A fetus that has not reached its growth potential. (in practice, small for gestational age (SGA) is often used as a proxy for FGR)
• Small for gestational age (SGA) Estimated fetal weight/birthweight less than 10th centile
• Severe FGR: Often SGA <3rd centile, features such as oligo/abnormal dopplers etc (oligohydramnios late sign of poor placental perfusion).
• Early onset: <32 weeks gestation
• Late onset: >32 weeks

2

When to suspect suboptimal fetal growth?

• The abdominal circumference on the population (ASUM) scan chart is <5th centile
• Discrepancy in HC and AC
• AC is >5th but is crossing centiles by > 30th centile e.g. reduction from 50th centile to 20th centile
• A change in AC of <5mm over 14 days
• EFW on GROW is <10th
• EFW on GROW is crossing centiles with > one third reduction in EFW percentile

3

What information should be gained from women with suspected FGR?

1. maternal characteristics and medical history (a history of a previous SGA or stillborn infant; maternal age >40; maternal or paternal history of being SGA at birth; smoking >10 cigarettes daily; using cocaine, and maternal diseases associated with increased risk (e.g. chronic hypertension, renal disease, diabetes with vascular disease, anti-phospholipid syndrome)

2. previous obstetric history (3x increased risk)

3. risk factors that may arise in pregnancy (low PAPP-A, heavy early pregnancy bleeding, fetal echogenic bowel, preeclampsia, severe pregnancy-induced hypertension, unexplained APH or abruption and low gestational weight gain)

4

Prevention

Start low dose aspirin (100-150mg) in those with risk factors for FGR if <16/40

5

What factors indicate regular growth scans rather than relying on SFH?

.Raised BMI
large fibroids
prev SGA
HTN disorder
Multiple pregnancy

6

Suspicion FGR, which investigations?

PET screen including urine,
USS growth +/- dopplers,
CTG,
TORCH and karyotyping if early onset severe SGA (especially if uterine/umbilical dopplers normal),
Consider fetal abnormality/chromosomal causes also in early onset.

7

How to manage babies once born if the have FGR/SGA?

- Monitoring and maintenance of oxygenation, temperature and blood glucose levels.
- Paired cord blood gases can be undertaken to assess acid base status at birth.
- In the care of the preterm growth restricted neonate, consider specific issues relating to prematurity such as lung disease, increased risk of infection, neurological complications and necrotising enterocolitis.
- Term babies at increased risk of hypothermia, hypoglycaemia and jaundice

8

Advice for future pregnancies?

Adjust any modifiable risk factors (e.g. smoking), aspirin for future pregnancies, serial growth scans
Uterine artery doppler

9

What does umbilical artery doppler measure?

Umbilical artery Doppler provides a measure of placental resistance.

10

What does MCA doppler measure?

MCA provides information about cerebral redistribution of blood flow, abnormal MCA is a response to hypoxia and means there is an increased proportion of flow to the brain- brain sparing.

11

What does DV doppler measure?

DV provides information about cardiac redistribution- abnormal DV associated with imminent fetal death.

12

Technique for UA doppler assessment?

• Free loop of cord (away from insertions)
• No fetal body, limb or breathing movements
• Identify UA with colour Doppler
• Measure FVW with pulsed Doppler
- set gate size to cover entire vessel
- Ideally display arterial and venous waveforms simultaneously
• Adjust Doppler gain, baseline, scale and sweep speed to produce a good quality FVW
• Analyse FVW to calculate S/D ratio or PI

13

Indications for measuring uterine artery doppler

• In women assessed to be at high risk of severe or early SGA
E.g:
- previous early SGA with delivery <34/40,
- antiphospholipid syndrome,
- severe chronic HTN,
- maternal renal disease
- an autoimmune condition)

14

Which gestation to perform uterine artery dopplers as screening?

20-24/40

15

Significance of abnormal uterine artery doppler?

Those with very abnormal uterine artery dopplers have a 60% risk of developing SGA/PET that requires delivery <34/40.

Should have regular scans and maternal surveillance.