Foetal Growth Restriction

Question 1

Define Fatal growth restriction (FGR)

Answer 1

Failure of the fetus to achieve its predetermined growth potential for various reasons

Question 2

Define small gestational age (SGA)

Answer 2

Birth weight <10th centile

Question 3

Describe low birthweight babies

Answer 3

Most LBW neonates are NOT growth restricted
Many FGR babies are delivered prematurely
3-10 fold increase in perinatal morbidity and mortality
LBW, FGR and preterm delivery have closely associated pathologies

Question 4

Which centile is the most sensitive

Answer 4

10th is the most sensitive

The tenth centile will capture all babies with FGR, but will also include those babies that are just small for gestational age, i.e. you get a number of false positives.

Question 5

Which centile is the most specific

Answer 5

3rd is the most specific
All babies recorded using the third centile will have FGR, but some FGR babies may be missed, i.e you get a number of false negatives.

Question 6

What is the difference between gestational age and foetal age

Answer 6

GA is 2 weeks greater than FA. FA starts post fertilisation

Question 7

What is the most common factor identified in stillborn babies

Answer 7

Intrauterine growth restriction (IUGR)

Question 8

What are the consequences of Intrauterine growth restriction (IUGR)

Answer 8

it has serious consequences for babies who survive.

There is an increased risk of IUGR and intrauterine death (IUD) in mother’s subsequent pregnancy.

Question 9

What are the short term problems of LBW/FGR

Answer 9

Respiratory distress
Intraventricular haemorrhage
Sepsis
Hypoglycaemia
Necrotising enterocolitis
Jaundice
Electrolyte imbalance

Question 10

What are the medium term problems of LBW/FGR

Answer 10

Respiratory problems
Developmental delay
Special needs schooling

Question 11

What are the long term problems of LBW/FGR

Answer 11

Foetal programming

Question 12

What are the maternal causative factors of FGR

Answer 12

Smoking 
Diabetes 
Anaemia 
<16 
>25

Question 13

What are the foetal causative factors of FGR

Answer 13

Multiple pregnancy
Chromosome abnormality
Inborn errors of metabolism

Question 14

Which weeks are the period of placentation

Answer 14

10-12 weeks

Question 15

Describe the placenta as an endocrine organ

Answer 15

Produces protein-peptides and steroid hormones and functions as a “transient hypothalamo-pituitary-gonadal axis”

Question 16

What are the functions of the placenta

Answer 16

Maintains immunological distance between mother and fetus

Responsible for exchange of nutrients, gases + metabolic waste products between maternal and fetal circulation

Question 17

Define pre-eclampsia

Answer 17

Multisystem disease that usually manifests as hypertension and proteinuria
BP > 140/90mmHg
Proteinuria > 0.3g/24hour (PCR>30)

Question 18

Describe the development of the placenta

Answer 18

1. Cytotrophoblast (CTB) invade syncytial (STB) and form villi which attach to the endometrium
2. The CTB continues to grow forming a CTB shell which forms the placenta. 3. The villi grow deeper into the myometrium until they come into contact with maternal spiral arteries
3. Spiral artery remodelling: CTB invade these arteries and cause them to become wider.

Question 19

How does pre-eclampsia lead to IUGR

Answer 19

Normal exchange of nutrients is not possible

Due to inappropriate spiral artery remodelling

Question 20

Which foetuses need growth monitoring

Answer 20

bad maternal obstetric history

Concerns in index pregnancy

Question 21

What may constitute a bad obstetric history

Answer 21

Previous maternal hypertension
Previous FGR
Stillbirth
Placental Abruption

Question 22

What may cause concern in index pregnancy

Answer 22

Abnormal serum biochemistry (PAPP-A < 0.3)
Reduced symphysis fundal height
Maternal systemic disease e.g. hypertension, renal, coagulation
Antepartum haemorrhage

Question 23

When is screening of “at risk” pregnancies carried out

Answer 23

24 weeks

Question 24

What is screened for in “at risk” pregnancies

Answer 24

PAPP-A < 0.3 MoM
POHxPET/FGR
Maternal systemic disease e.g. HT< renal, sickle
Uterine artery Doppler in 1st/2nd trimester (blood flow in uterine arteries -> find high resistance flow)

Question 25

When is delivery aimed for

Answer 25

≥28 weeks

and / or ≥500g

Question 26

Describe the delivery in pregnancies complicated by FGR

Answer 26

Timing delivery in these pregnancies depends on balancing the risks to the fetus if it remains in utero and the hazards from the prematurity, which decrease as the gestation advances

Question 27

What is required if the baby is born less than 36 weeks

Answer 27

Corticosteroids

Question 28

Is late IUGR or early IUGR easier to manage

Answer 28

Late

Early IUGR: 1%, usually linked to maternal disease e.g. PEC, difficult to manage because of risk of prematurity

Late IUGR: 5-7%, rarely linked to PEC, difficult to differentiate from SGA, easily managed by delivery

Question 29

Describe the growth of the baby if a dating problem is the cause of SGA

Answer 29

Consistent growth

Normal dopplers and fluid

Question 30

Describe normal growth

Answer 30

Growth may reduce in 2 weeks

Normal dopplers and fluid

Question 31

Describe the growth of the baby if SGA is caused by a foetal problem

Answer 31

Fetal abnormality

Question 32

Describe the growth of the baby if placental insufficiency is caused by a foetal problem

Answer 32

Reduction in AC/FL
Reduced liquor
Deranged doppler