Small & Large Births

Question 1

What are the 2 main causes for a small baby?

Answer 1

Pre-term delivery
Small for gestational age due to intrauterine growth restriction (IUGR) or simply constitutionally small!

Question 2

How is a birth defined as preterm?

Answer 2

Delivery between 24-36 weeks gestation

Question 3

List some causes of preterm birth

Answer 3

Infection
Overdistention (multiple pregnancy)
Placental abruption
Cervical incompetence
Idiopathic

Question 4

How is a baby defined as being small for gestational age?

Answer 4

Birthweight less than 10th centile for gestation, corrected for maternal weight, height, foetal sex and birth order

Question 5

What maternal factors cause poor growth of a foetus?

Answer 5

Lifestyle: smoking, drugs, alcohol
BMI 19 or less
Extremes of age
Disease: hypertension

Question 6

What foetal factors cause poor growth of a foetus?

Answer 6

Infection: rubella, CMV
Congenital anomalies
Chromosomal abnormality

Question 7

What are the consequences to the foetus if there is growth restriction?

Answer 7

Hypoxia
Hypoglycaemia
Asphyxia
Hypothermia
Polycythaemia
Abnormal neurodevelopment

Question 8

What are some clinical indicators of poor growth?

Answer 8

Fundal height less than expected
Reduced liquor (low amniotic fluid)
Reduced foetal movements

Question 9

What is cardiotocography used for?

Answer 9

Measure foetal heartbeat

Question 10

What are the main aetiology behind large babies?

Answer 10

Wrong date
Multiple pregnancy
Diabetes
Polyhydramnios

Question 11

What is polyhydramnios?

Answer 11

Excess amniotic fluid

Question 12

What causes polyhydramnios?

Answer 12

Monochorionic twin pregnancy
Foetal anomaly
Diabetes
Hydrops fetalis

Question 13

What is the difference between zygosity and chorionicity?

Answer 13

Zygosity: number of eggs fertilied to produce twins
Chorionicity: membrane pattern of the twins

Question 14

Which is the outer layer - chorion or amnion?

Answer 14

Chorion outside
Amnion inside

Question 15

Describe a dichorionic diamniotic pregnancy

Answer 15

Each foetus has its own amniotic sac and its own placenta

Question 16

Describe a monochorionic diamniotic pregnancy

Answer 16

Each foetus has its own amniotic sac but shared placenta

Question 17

Describe a monochorionic monoamniotic pregnancy

Answer 17

Both foetuses share amniotic sac and placenta

Question 18

Multiple pregnancies carry higher perinatal mortality due to what?

Answer 18

Congenital anomalies
Preterm labour
Growth restriction
Pre-eclampsia
Twin-twin transfusion

Question 19

How are triplets usually delivered?

Answer 19

Caesarean section

Question 20

Describe the pathophysiology of gestational diabetes mellitus

Answer 20

Placental hormones cause insulin resistance in the mother, causing hyperglycaemia

Question 21

How does gestational diabetes lead to macrosomia?

Answer 21

Overgrowth of insulin sensitive tissues due to hyperinsulinaemia

Question 22

What are the diagnostic glucose values for gestational diabetes (fasting and 2-hour)?

Answer 22

Fasting: 5.6 mmol/l or more
2-hour: 7.8 mmol/l or more