Foetal growth

Question 1

What 2 main groups of factors influence foetal growth?

Answer 1

Intrinsic - genetic (cannot do anything about)

Extrinsic - environmental

Question 2

What is the difference between miscarriage and stilllbirth?

Answer 2

up to 24 weeks: miscarriage

after 24 weeks: still-birth

Question 3

Why is foetal growth important?

Answer 3

Can indicate risk of still birth

Question 4

What are some maternal extrinsic factors effecting foetal growth?

Answer 4

social class (smaller babies, higher risk of still born)

nutritional status

environment: altitude

pre-existing disease: cardiac/renal/respiratory/vascular

pregnancy-related disease:
hypertension (small babies), diabetes (big babies)

Question 5

What are some foetal extrinsic factors effecting foetal growth?

Answer 5

nutrition: placental
teratogenic: tobacco, narcotics, alcohol, medication

infective:
 - viral: 
rubella (small babies), CMV (small babies) (V-Z, measles, hepatitis A and B)
 - protozoan : toxoplasma (small babies)
 - others: listeria, syphilis

Question 6

What are some intrinsic factors effecting foetal growth?

Answer 6

Maternal:
height and weight
parity (more pregnancies = bigger babies)
ethnic group

Fetal:
sex
genes/inherited conditions

Question 7

What happens if a midwife thinks the baby is small?

Answer 7

Midwife will refer mother to obstetrician

Question 8

What things would you ask a mother who has reduced foetal growth?

Answer 8

Hx of small babies

Medical conditions
Medicines
Smoking, alcohol
nutrition
general fitness etc.

Foetal movements (from about 26 weeks)

Question 9

How would you examine a woman who has reduced foetal growth?

Answer 9

General assessment
Obstetric examination: fundal height
liquor volume

Question 10

What is SGA?

Answer 10

small for gestational age:

Foetus that has failed to achieve a specific biometric or estimated weight threshold by a specific gestational age

Question 11

What small babies would you not be worried about?

Answer 11

Constitutionally small babies

Question 12

What would you be concerned about in a small baby that is not just constitutionally small?

Answer 12

intra-uterine growth restriction

Question 13

How do you measure the growth of a baby?

Answer 13

BPD: biparietal diameter
HC: head circumference - plot on graph to see whether this is normal or not
AC: abdo circumference
FL: femur length

Question 14

After how long are growth scans usually repeated if IUGR is suspected?

Answer 14

2 weeks

Question 15

If a baby has IUGR, what does their AC graph usually look like?

Answer 15

plateau, rather than curve

Question 16

If a baby has a normal HC, but small AC, what is this called? What does this indicate?

Answer 16

Head-sparing effect - more blood goes to head, therefore abdo and chest do not grow as well

IUGR

Question 17

What are we worried about in IUGR?

Answer 17

placenta will shut down

Question 18

What is another name for a growth scan?

Answer 18

foetal assessment scan

Question 19

Other than measuring the baby, what else is done in a foetal assessment scan? What are other ways people might assess foetal development?

Answer 19

BPP: biophysical profile

• fetal breathing movements
• fetal movements
• fetal tone
• amniotic fluid volume (reduced because less blood to baby’s kidneys, therefore reduce urine output)

ASK WHAT THE MOTHER THINKS IS HAPPENING RE. MOVEMENT

Kick charts

Heart rate monitoring (CTG)

Assess baby’s feeding (placental assessment): Doppler studies

Question 20

How do we assess the placenta in foetal assessment?

Answer 20

umbilical and uterine flow doppler studies:
appearance
blood flow characteristics

foetus to placenta: umbilical
mother to placenta: uterine

Question 21

What are the important readings taken from doppler study?

Answer 21

Pulsatility index and resistance index

Question 22

What does a progressively greater resistance index found on a doppler scan lead to?

Answer 22

absent or reversed EDF

Question 23

What should be shown on a umbilical Doppler ultrasound?

Answer 23

Blood flow should take place during systole and diastole.

If there isn’t (or worse, LOSS of blood) = VERY WORRYING

Question 24

What are the two main causes of SGA babies?

Answer 24

Constitutionally small

IUGR