4b: Intra-Uterine growth Restrictions

Question 1

What is Small for gestational Age? (SGA)?

Answer 1

he infant has a birth weight <10th centile (also called ‘Small for dates’).

Question 2

What is IntraUterine growth resticion (ICGR)?

Answer 2

Failure of the infant to achieve its predetermined (genetic) potential for a variety of reasons

Question 3

Define Low Birth weight

Answer 3

Less than 2,500g at delivery. Currently ~7% of live births (UK).

Question 4

Define Very low birth weight

Answer 4

Less than 1,500g at delivery. Currently ~1% of live births (UK).

Question 5

Define Extremetly low birht weight

Answer 5

Less than 1,000g at delivery. Currently ~0.2% of live births (UK).

Question 6

When trying to define babies with IUGR, which percintiles to you use as guidance?

Answer 6

Depending on what you want

1. 10th centile: high sensitivity (will pick up all babies) but also many healthy
2. 3rd centile: highly specific but will miss IUGR babies

Question 7

How can IUGR be assessed?

Answer 7

should only be used for fetuses with definite evidence that growth has altered

–> Percentile deviation from series of observations should be used!

Question 8

What are the different outcomes that might happen from IUGR

Answer 8

Widely increases change of stillbirth

• subsequent pregnagncies might also be affected and have an increased riks
• increased numer of complications:
  
  • short term
  • medium term
  • long term

Question 9

What are the short term probems of IUGR?

Answer 9

• Respiratory distress
• Intraventricular haemorrhage
• Sepsis
• Hypoglycaemia
• Necrotising enterocolitis
• Jaundice (when loosing weight)
• Electrolyte imbalance

Question 10

What are the medium-term consequences of IUGR?

Answer 10

• Respiratory problems
• Developmental delay
• Special needs schooling

Question 11

What are the long term problems of IUGR?

Answer 11

Fetal programming –> might still have problems in adut life

Question 12

When do IUGR ususally develop?

Answer 12

Usually in 2nd and 3rd trimester (where most growht happens)

Question 13

What are the main categories of factors that can influence IUGR

Answer 13

1. Maternal Behaviour
2. Maternal Medical factors
3. Fetal factors
4. Placental Factors

Question 14

Which maternal medical factors might lead to the developent of IUGR?

Answer 14

• Chronic hypertension
• Connective tissue disease
• Severe chronic infection
• Diabetes mellitus
• Anaemia
• Uterine abnormalities
• Maternal malignancy
• Pre-eclampsia
• Thrombophilic defects

Question 15

What is pre-eclampsia?

What is the consequence

Answer 15

Condition that is characterised by

• development of Maternal HTN
• And Proteinuria
• After 20 weeks
• Cause unknown but
  
  • fibrous spiral arteries –> abnormal placenta
    
    • leading to inflammation –>
    • endothelial alteraltion of maternal organs leading to vasoconstriction
• Might lead to IUGR and miscarriage, displacement of placenta

Question 16

What are maternal behavioural factors that might cause IUGR?

Answer 16

• Smoking
• Low booking weight (<50 kg)
• Poor nutrition
• Age <16 or >35 years at delivery
• Alcohol
• Drugs
• High altitude
• Social deprivation

Question 17

What are fetal factors that might lead to IUGR?

Answer 17

• Multiple pregnancy
• Structural abnormality
• Chromosomal abnormalities
• Intrauterine (congenital) infection
• Inborn errors of metabolism

Question 18

What are placental factos that might lead to IUGR?

Answer 18

• Impaired trophoblast invasion
• Partial abruption or infarction
• Chorioamnionitis
• Placental cysts
• Placenta praevia

Question 19

How is pre-eclampsia managed?

Answer 19

Very hard to treat so main aim:

• Monitor and
• Time the right time for delivery
  
  • ggf. consider corticosteroids to help development of fetus

Question 20

Which factors are monitored in pre-eclapsia and considered to time the right time for delivery?

Answer 20

Doppler assessment of Arteries

• uterine artery
• umbilical artery
• fetal middle cerebral artery
• ductus venosum
  
  • Are also indicators of metabolic status

Fetal movements (reduction might precede fetal death)

• done by Cardiff Kick chart and/or
• CTG

Question 21

Explain the sequence of events in IUGR that might lead to Fetal Death

Answer 21

Question 22

Explain the effects of Hypoxia in the fetus

Answer 22

Question 23

What is the Ductus Venosus?

How might it be used in prediction of IUGR?

Answer 23

Longitudinal through upper abdomen
• Parallel, anterior to the right of the aorta • Receives 40% of umbilical venous flow
• Directs oxygenated blood to the L ventricle

• Change its Doppler screening in Hypoxia/Acidosis

Question 24

Compare early vs late IUGR

Answer 24