Fetal Growth And Development Flashcards
What generally happens during the fetal period?
Growth and physiological maturation of the structures created during the embryonic period
Involves preparation for the transition to independent life after birth
When does crown-rump length increase the most?
During the pre-embryonic, embryonic and early fetal period
When is the rate of weight gain at its highest?
Mid and late fetal periods
What is deposited in the early and late fetal periods?
Early - protein deposition
Late - adipose deposition
How much of the lungs does embryonic development produce?
Bronchopulmonary tree
What are the names of the stages of development of the lungs and and which weeks is each one?
Pseudoglandular stage - week 8-16
Canalicular stage - week 16-26
Terminal sac stage - week 26-term
What happens during the pseudoglandular stage? (Week 8-16)
Duct system of the lungs begins to form within the bronchopulmonary segments created during the embryonic period to form bronchioles
What happens in the canalicular stage of development of the lungs (week 16-26)
Formation of respiratory bronchioles
Budding from bronchioles formed during the pseudoglandular stage
What happens during the terminal sac stage of development of the lungs?
Terminal sacs begin to bud from respiratory bronchioles
Get differentiation of type I and II pneumocytes
Surfactant production
How are the lungs prepared for birth during T2 and T3
Breathing movements to condition respiratory musculature
Fluid-filled which is crucial for normal lung development
What is the threshold of viability and when is it?
Viability only possible once lungs have entered the terminal sac stage of development
So after 24 weeks
What is respiratory distress syndrome?
How can you increase fetal surfactant production?
When babies are born pre-maturely, can have insufficient surfactant production
If preterm delivery it is unavoidable, give glucocorticoids to mother to increase fetal surfactant production
What is fetal bradycardia associated with?
Fetal demise
When does fetal kidney function begin?
Week 10
What happens if there is fetal kidney dysfunction?
Oligohydraminos
What can cause oligohydraminos?
Placental insufficiency
Fetal renal impairment
What can cause polyhydraminos?
Fetal abnormality eg inability to swallow
Which system is the first to begin development and last to finish?
Nervous system
When do corticospinal tracts begin to develop and what are they necessary for?
4th month
Required for co-ordinated voluntary movement
When does myelination of the brain begin?
9th month
When is first movement seen?
Week 8
What movements develop during the fetal period?
Suckling
Breathing
Implications of fetal movement?
Noticed by mother from week 17 onwards
Low cost simple method of ante-partum fetal surveillance
Reveals fetuses requiring follow up
Describe the development of the kidneys during the fetal period
Function after ascent is finished in week 10
Renal pelvis and calyces present by week 23
Histological differentiation of cortex and medulla is almost complete by 8 months