Fetal Growth - Types and Problems Flashcards
(52 cards)
What are the four types of fetal growth?
1) AGA - appropriate for gestational age
2) SGA - small for gestational age
3) FGR/IUGR - fetal growth restriction
4) LGA - large for gestational age
What is FGR?
- Starved baby
- Inconsistent growth
When are we not concerned about a SGA baby/healthy small baby?
- If growing consistently at 10% centile, just a small baby
- Constitutionally small
- Small parents
What are causes of an intrinsically small SGA baby?
1) Chromosomal abnormality e.g. T21, T18, T13
2) Infectious e.g. CMV
3) Environmental e.g. fetal alcohol syndrome
What are the 3 types of SGA baby?
1) Intrinsically small
2) Growth-restricted small
3) Healthy small
What are the causes of a growth-restricted small SGA baby (FGR/IUGR)?
1) Insufficient nutrient delivery gas exchange (placenta)
2) Maternal vascular disease e.g. HT, PET, DM
3) Maternal decrease O2 capacity e.g. sickle cell
4) Placental damage e.g. smoking
What are the 3 types of causes of IUGR?
1) Mother - chronic illness, smoking, drugs, alcohol
2) Placenta - pre-eclampsia
3) Baby - congenital abnormality
What is the definition of a SGA infant?
Birth weight < 10th centile
What is the definition of a SGA fetus?
EFW or AC < 10th centile
What is severe SGA?
- Fetus EFW or AC < 3rd centile
- Higher chance of FGR
What is FGR/IUGR?
- SGA baby with evidence of compromise e.g. amniotic fluid or changes with doppler
- Pathological restriction of genetic growth potential
- May have evidence of fetal compromise e.g. abnormal AFI or dopplers
- Has increased risk of perinatal complications
What perinatal complications are FGR babies at increased risk of?
1) Stillbirth
2) Seizures
3) Apgar score < 4 - poor prognosis sign
4) Cord pH < 7.0
5) Admission to intensive care
6) Hypothermia
7) Hypoglycaemia
What is the Apgar score and when is it given?
- Test given to newborns soon after birth which checks a baby’s heart rate, muscle tone, and other signs to see if extra medical care or emergency care is needed
- At 1 minute, 5 minute and 10 minute after birth
- < 4 is a poor prognosis sign
What are the perinatal outcomes of SGA babies?
Similar to AGA babies
What might FGR babies benefit from?
Being delivered early
What are long term consequences of FGR?
- Coronary heart disease
- Cerebrovascular accident (CVA) = stroke
- T2D
- Hypertension
How does the NHS aim to halve the rate of stillbirth?
1) Reducing smoking in pregnancy
2) Risk assessment and surveillance for fetal growth restriction
3) Raising awareness of reduced fetal movement
4) Effective fetal monitoring during labour
What are risk factors for an SGA fetus?
1) Current/demographic risks
2) Previous pregnancy risks
3) Maternal medical history
4) Current pregnancy complications
Is SGA fetus screened for?
Yes (look at diagram in notes if want to know more)
What is PAPP-A?
- Pregnancy associated plasma protein A
- Assessed as part of the firs trimester combined screen
What do low levels of PAPP-A indicate?
- Associated with poor placentation - poor implantation or formation
- Low PAPP-A (<0.4MoM) means there is an increased risk of SGA/pre-eclampsia (PET)
How would you manage a patient with PAPP-A < 0.4?
1) Give aspirin 75mg once a day
2) Arrange growth scans e.g. at 26-28 weeks and 34-36 weeks
What is a uterine artery doppler?
- Maternal artery measurement
- Can be done in 1st trimester or 20-24 weeks
What do uterine artery doppler results indicate?
- Low resistance to flow is reassuring (not peaks)
- High resistance to flow at 24 weeks = PI > 1.4 - increased risk of SGA/PET
- High peaks = high resistance flow, indicating redistribution of blood e.g. to brain