Prenatal Flashcards
(22 cards)
Germinal Period: The First 14 Days
→ zygote travels towards uterus
Divides and forms blastocyst
- 16 to 64 cells by the time it gets to the uterus
Blastocyst implants itself in the uterine wall
- This signifies the change to a new phase
The time period a morning after pill would work, increases the amount of hormones that would make it inhospitable for the zygote to reach the uterus
- Blastocyst ends up getting flushed out in the period
Embryonic Period: 3rd to 8th Week
Blastocyst implants in the uterine wall
- Period of organogenesis
Layers of cells differentiate to become
- Ectoderm (outer layer
Nervous system, skin, hair - Mesoderm (middle)
Bones, muscles, circulatory system - Endoderm (inner)
Digestive system, lungs, urinary tract and other vital organs
Risk Factors during Embryonic Period
→ during this period, the fetus is most likely to be impacted, alcohol, miscarriage etc
Embryology after 4 Weeks
- A lot of the vital organs start to develop,
- Some of the beginnings of limbs, arms and legs
- Precursors to the brain
Embryology after 6 weeks
head is almost half the volume of the embryo
Embryology after 8 weeks
- Head still taking at least ⅓ volume of the fetus
- Internal organs are formed and starting to function
Changes between Embryonic and Fetal Period
Between embryonic and fetal periods is when real bone starts to replace cartilage in the limbs
- Culturally the Gestation Period is split in three parts, treating them all the same, however the first 8 weeks is the most important for the fetus
The Fetal Period
- Period of rapid growth and refinement of organ systems
- Fetus more responsive
- Behaviour becomes increasingly regular and integrated
Fetuses become viable between 22-28 weeks
- Viability refers to the 50% chance of survival that they will survive after birth
- Limit of viability is 24 weeks
- As low as 22 weeks, as their are variability in risk factors that produce different results
Fetal Period at 12 weeks
- One third of the total volume in the head still
- Sex differentiation occurs
- Mother doesn’t feel the movement in the womb
Fetal Period at 18 weeks
- Most rapid growth in the physical size
- Mother can feel the child
start behaviours that are most infant like - Theorised that the sucking of the thumbs by the fetus might prepare the baby to get ready to breath in the real world, practicing their respiratory system
Fetal Period at 6 months
- Capable of responding to light
- Bones of inner ear form, can now hear sounds
- 75db in the uterus
- Mother’s voice and heartbeat are best heard
Cat in the Hat Study
Mums asked to read the Dr Seus book twice a day for the last 6 weeks of their pregnancy
- After birth they tested response the book with operant conditioning
- Given a feeding nibble, like that of a breast, and then had headphones placed on them, one that had the audio of the mother reading Cat in the Hat or another random person, or Mum reading a different story
- Babies found that they can change the sucking rate to change the sound
- More likely to change the sucking rate, when they found that their Mum was reading Cat in the Hat
Fetal Period at 7 months
Fetus begins putting on weight in the form of fat just beneath the skin
Respiratory system is risky
- Babies between 30-32 have worse outcomes than those born after, because the lungs produce surfactant during this stage (surfactant keeps air pockets of the lungs open when you breath out)
- Sometimes doctors will try to prevent the baby from being born, try to make sure the lungs are mature as possible
The Preterm Infant
- Born at 36 weeks or earlier
- Low birth weight (<2500g)
- May have developmental difficulties as well
Potential Contributors to preterm Risk Factors
- Likelihood of preterm births increase in women who used to not be able to conceive
- More and more common to have preterm births in US,
Shifted from 40 weeks to 39 weeks - Likely due to fertility treatments such as IVF
Factors of Preterm infancy in Australia
7% of all births <37 weeks
- Indigenous mothers, suspected likely because of a lack of access to quality care
- Young mothers (less than 20), possibly less conscientious
- Older mothers (more than 40), uterine environment and fertility treatment risks
- Multiple births, less space and resources shared
- First time mothers, unsure why
Limit of Viability
→ age at which infants have a 50% chance of surviving their first year
- At 23 weeks, 74% chance of dying before 2 years
- At 24 weeks, 44% chance of dying before 2 years
What does research suggest we should consider, in relation to preterm infancy?
- Birth weight
- Gender, girls may do better, possibly to do with the role of estrogen in lung development
- Multiple or singleton
- Steroids
E.G at 23 Weeks
- Relatively heavy girl, singleton +steroids = 80% survival
- Relatively small boy, twin + no steroids = 20% survival
NICU (Neonatal Intensive Care Unit) Video
- Babies in intensive care will later struggle with attention, learning, structure and so forth
- Best efforts are not completely comparable to full term births, why
- Life in the womb than those forced outside, accesses food from the digestive system, more support for their body than a bed, doesn’t have to breath on her own etc
- Carefully controlled environments will help foster stronger children
- Placed on top of mother, skin to skin contact, create a dark environment, hears heartbeat
Interventions in NICU
- Try to emulate the environment of the womb with containment and lighting
- Wrapped tight as possible with the same lack of space as the womb
- Low light scenarios
Kangaroo Care
- Skin-to-skin contact with mother
Accelerates development of regulatory processes (Feldman & Eidelman)
- Sleep development
- Better feeding/growth
- Earlier discharge
- Nice for parents to feel like they have a role to play in their child’s development
Tactile-kinesthetic Stimulation
Type of Massage
- Stimulates growth, metabolism enhanced
- Decreases stress behaviours
- Earlier discharge
- Mainly for postnatal depressed mothers
- Involves passively moving the limbs, pressing lightly etc
