IUGR

Question 1

What is IUGR?

Answer 1

Failure of foetus to achieve its growth potential

Question 2

What is SFD?

Answer 2

Small for dates. BW

Question 3

What is the short term clinical significance of IUGR?

Answer 3

Increased incidence of:

• Preterm labour
• Perinatal mortality (stillbirths, neonatal deaths)
• Neonatal morbidity (hypothermia, infection, hypoglycaemia, irritable and poor feeders, meconium aspiration)

Question 4

What is the long term clinical significance of IUGR?

Answer 4

Increased:

• Childhood long term morbidity (motor / intellectual handicap)
• Adulthood morbidity and mortality (DOAD)

Question 5

What is DOAD?

Answer 5

Developmental origins of adult disease (Barker hypothesis).
Birthweight is inversely related to risks of:
-HTN
-DM
-Dyslipidemia
-Vascular disease a/w above

Question 6

What are the foetal sources of IUGR?

Answer 6

• Chromosomal: chromosomal, single gene d/o, structural anomalies, familial
• Infections

Question 7

What are the maternal sources of IUGR?

Answer 7

• Vascular disease
• Thrombophilia
• Toxins
• Cardiac disease
• Malnutrition
• Anaemia
• Atmospheric respiratory hypoxia / high altitude
• Infection (rubella, VZV, CMV)
• Smoking, alcohol, substance use

Question 8

What are the placental sources of IUGR?

Answer 8

• Multiple pregnancy
• Abruption
• Placental abnormalities

Question 9

What are the methods of screening for IUGR?

Answer 9

• Symphyseal fundal height (2/3 of SFDs detected, intra observer reliability > inter)
• US (more effective, optimal at 34 weeks)

Question 10

What is the management of IUGR?

Answer 10

• Confirm Dx (IUGR or genetically small)
• Aetiology Dx and Rx
• Foetal surveillance
• Therapy
• Delivery

Question 11

What are the factors in diagnosing being genetically small (as part of confirming diagnosis)?

Answer 11

• Parental small stature
• absence of recognised risk factors
• Symmetrically small
• Normal growth trajectory
• Biophysically active
• Normal amniotic fluid
• Normal umbilical and other doppler studies

Question 12

Why is early IUGR especially significant?

Answer 12

Early in pregnancy foetal growth occurs primarily through hyperplasia; early onset IUGR may lead to irreversible diminution of organ size / function.

Question 13

Which medications are associated with IUGR?

Answer 13

• Anticonvulsants
• Warfarin
• Folic acid antagonists

Question 14

What are the standard foetal size assessment on US?

Answer 14

• 1) Biparietal diameter
• 2) head circumference
• 3) Abdominal circumference
• 4) Femur length

Question 15

Why is amniotic fluid volume assessed on US in IUGR evaluation?

Answer 15

Combination of oligohydramnios (dec amniotic fluid volume) and IUGR a/w significant morbidity and mortality

Question 16

What is the mechanisms of decreased amniotic fluid?

Answer 16

Thought to be decreased placental perfusion of O2 and nutrients, compensatory redistribution of foetal blood to heart, adrenal and brain.
Decreased renal perfusion = decreased amniotic fluid due to limited urine output.