Foetal Growth and Development Flashcards
What happens during the foetal period
Growth and physiological maturation of the structures created during the embyronic period
Prepares for transition to independent life after birth
From 9th wk to term
What measurements can be used to estimate the size of the baby
Crown-rump length
Symphysis-fundal height
How does weight gain change through the foetal periods
Embryo - little weight gain. Mainly morphogenesis and differentiation. Placental growth
Early foetus - protein deposition
Late foetus - adipose deposition
How can the mother be aware of how well her baby is
Mother is aware of foetal movements -> knows what is normal for her baby
How do we measure the symphysis-fundal height and why is it used
Measure from the fundus (top) of the uterus to the symphysis pubis of the mother
Used as during pregnany there is regular expansion of the uterus due to regular growth of the foetus -> as foetus grows, uterus expands
What sources of error are there in using symphysis-fundal height as a way to determine week of gestation
If there are abnormalities in amniotic fluid production - polyhydramnios, intrauterine growth restriction or oligohydramnios
Hard to measure in obese
If there are twins - not usually same height as if there was a single baby
Fundal height can drop a couple of weeks before birth
Position of the foetus
What method is used most often to measure foetal well-being
Ultra sound scan
What can an USS be used to measure/assess
Calculate age
Rule out ectopic
Number of foetuses
Viability of foetus
Abnormalities
Biparietal diameter
Abdominal circumference
Femur length
Organ development - including heart, spinal cord and facial features
At what week is an USS carried out at and why is this week used
Carried out at 20wks
Good as organs will have formed by 20th week -> can check viability, location and number
What methods are used to estimate foetal age
Last menstrual period
Developmental criteria
What criteria are used as part of the developmental criteria in estimating foetal age
Crown-rump length
Biparietal diameter (BPD) - distance between parietal bones of skull
Abdominal circumference and femur length - used in combination with BPD for dating and growth monitoring
3- or 4-D USS
What is used to monitor a foetus with a growth restriction and what parameters are used
Bio physical profile - uses parameters which relate to development and function of foetal organ systems:
- Foetal movement
- Foetal breathing movement
- Foetal tone
- Amniotic fluid volume
- Foetal heart rate in response to movement in the non-stress test
How is baby birth-weight classified
3.5kg is average
<2.5kg is underweight and suggests growth restriction
>4.5kg is macrosomia
Why might a baby have a low birth weight
Born prematurely
May be constitutionally small
May have suffered growth restriction
What factors need to be considered when deciding whether to allow a compromised foetus to remain in utero
Can mother fuction without the baby
Will the baby kill the mother if it remains in utero
Risk of prematurity
After 24wks, try to keep foetus in utero unless big risk to mother
Before 34wks, don’t want to deliver due to risk of prematurity
