Size At Birth

Question 1

What is classified as low birth weight?

Answer 1

Less than 2.5kg

Question 2

What percentage of babies in the UK are of low birthweight?

Answer 2

7%

However, they account for 70% of neonatal deaths

Question 3

Babies with a birth weight below the 10th centile for their gestational age are called..,

Answer 3

Small for gestational age or small-for-dates

Question 4

Are the majority of babies born small for gestational age, normal?

Answer 4

Yes they are normal but small

Question 5

The incidence of congenital abnormalities and neonatal problems is higher in those who’s birthweight falls below the …

Answer 5

Second centile - approx 2 standard deviations below the mean (some authorities restrict the term small for gestation age to this group)

Question 6

An infants birthweight may be low because of preterm birth or because the infant is both preterm and small for gestational age. True or false?

Answer 6

True

Question 7

Small for gestational age infants may have grown normally but are small, or they may have experienced what?

Answer 7

Inter uterine growth restriction (IUGR)

Question 8

What is IUGR?

Answer 8

When the baby has failed to reach their full genetically determined growth potential and appear thin and malnourished

Question 9

Can babies above the 10th centile be malnourished?

Answer 9

Yes e.g a fetus may be growing along the 80th centile and develop growth failure and weight then falls to the 20th centile

Question 10

Growth restriction in fetus and infant has been classified as…

Answer 10

Symmetrical or asymmetrical

Question 11

Is symmetrical or asymmetrical growth restriction more common?

Answer 11

Asymmetrical

Question 12

Describe asymmetrical growth restriction

Answer 12

The weight or abdominal circumference lies on a lower centile compared to that of the head

Question 13

Asymmetrical growth restriction occurs when..

Answer 13

The placenta fails to provide adequate nutrition late in the pregnancy but brain growth is relatively spared at the expense of liver glycogen and fat

Question 14

Asymmetrical growth restriction is associated with uteroplacental dysfunction secondary to..

Answer 14

Maternal pre eclampsia
Multiple pregnancies
Maternal smoking
Or can be idiopathic

Question 15

Do those with asymmetrical growth restriction put on weight after birth?

Answer 15

Yes rapidly

Question 16

What is asymmetrical growth restriction associated with later in life?

Answer 16

Increased obesity risk and type 2 DM later in life

Question 17

Describe symmetrical growth restriction

Answer 17

The head circumference is equally reduced

Question 18

What does symmetrical growth restriction suggest?

Answer 18

A prolonged period of poor intrauterine growth starting in early pregnancy (or that gestational age in incorrect)

Question 19

What is symmetrical growth restriction due to?

Answer 19

Usually small but normal fetus
May be due to a fetal chromosome disorder or syndrome, congenital infection, maternal drug and alcohol abuse, maternal chronic medical condition or malnutrition

Question 20

Are those with symmetrical growth restriction more or less likely to remain small permanently?

Answer 20

More likely

Question 21

In practice can the distinction between asymmetrical and symmetrical growth restriction be made?

Answer 21

No

Question 22

The fetus with IUGR is at risk from …

Answer 22

Intrauterine hypoxia and unexplained uterine death

Asphyxia during labour and delivery

Question 23

Progressive uteroplacental failure results in..

Answer 23

Reduced growth in femur length and abdominal circumference
Oligohydraminos from reduced fetal urine production
Abnormal umbilical artery Doppler waveforms
Redistribution of blood flow in fetus - increased to brain, reduced to GI tract, liver, skin and kidneys
Abnormal ductus venosus Doppler waveform from cardiac dysfunction
Reduced fetal breathing and movements
Abnormal fetal heart rate trace

Question 24

After birth, growth restricted infants are liable to…

Answer 24

Hypothermia due to their relatively large surface area (especially head)
Hypoglycaemia from poor fat and glycogen stores
Hypocalcaemia
Polycythemia

Question 25

Large for gestational age infants are those above what centile for their gestation?

Answer 25

90th

Question 26

What causes infants who are large for gestation age ?

Answer 26

Most are normal
Mother has DM type 1 or gestational diabetes
Congenital syndromes e.g Beckwith-Wiedemann syndrome

Question 27

What problems are the associated with being large for gestational age?

Answer 27

Birth trauma - especially from shoulder dystocia at delivery
Birth asphyxia from difficult delivery
Hypoglycaemia due to hyperinsulinism
Polycythemia
Breathing difficulty from enlarged tongue in Beckwith-Weidemann syndrome