Prenatal development Flashcards
Pregnancy contraindications
- Increased lordosis, belly weight (20-35lbs), pain, swelling, blood pressure,
- change in center of gravity, posture (compensatory and uncontrollable), thermoregulation
PTAs should be aware of (9) things in preggers
- Thermoregulation
- Blood volume
- Venus pressure in LE
- HR and BP baseline
- Preeclampsia
- Edema
- Excessive weight gain
- Headaches
- Vision disturbances
3 edu about preggers
- Abd muscles are compromised and affect respiratory and urinary systems
- Teach relaxation techniques
- Preggers can participate in activities and exercise, edu on BODY MECHANICS and listening to body. NO ANXIETY OR PAIN
Mechanisms of heredity
- 23 chromosome pairs (egg+sperm)
- 1 molecule of DNA per chromosome
- 22 pairs are autosomes
- 23rd pair sex chromosomes
- more or less than 46 = developmental delays
Genes
- regulate the development of all human characteristics and abilities
- determine production of chemical substances that are the oundation fro characteristics and abilities
Genotype
- complete set of genes that make up a person’s heredity
- produce phenotypes
- if the alleles are the same, thy typically produce that phenotype; if they are different, the dominant wins
Phenotype
Features that are produced from the interaction between genes and the environment
Either-or phenotypes
Traits that are controlled by a single gene
Polygenic inheritance
Many separate genes influence behavioral and psychological characteristics
- nature vs nurture
Genetics and behavior
- heredity and environment interact dynamically through development
- genes can influence the kind of environment to which a person is expose
- environmental influences typically make children within a family different
- *people seek ideal environments compatible with their capabilities/desires
3 stages of prenatal development
Zygote, embryo, and fetus
- trimesters
1. W 1-12
2. W 13-27
3. W 28-birth
Zygote stage
Conception to early implantation (w 1-2)
- newly fertilized egg
- 2 individual sets of 23 chromosomes are interchanged, one from each parent
- ends when the zygote implants in uterine wall (blood vessel connection)
Embryo stage
Once the zygote is embedded in the uterine wall = embryo W 3-8
- development includes:
- umbilical cord: blood vessels allow exchange of nutrients, oxygen, vitamins, waste products
- eyes, arms, and legs
- brain and nervous system
- heart started to beat around 4 weeks
- ** most sensitive to environmental toxins aka most crucial timeframe
Fetal stage
W 9-birth
- weighs less than an ounce and gains 7-8lbs
- all regions of the brain grow
- systems develop
- movement are now obvious- bursts of activity are followed by stillness until regular activity cycles emerge (following mom’s cycle)
- sense begin to work
- sensory experiences form memories (taste and sound)
Premies
Age of viability 22-28 weeks
- peds use gestational age rather than true age for milestones and integration of reflexes *behind because early birth
Labor and delivery
3 stages
- May last 12-24 hours. Dislates to 10 cm
- When baby passes through the cervix and enters the vagina. Within an hour baby is delivered
- After birth. Placenta is delivered
Immediate parenthood
Immediately after delivery breasts begin to produce milk, uterus becomes smaller, female hormones drop
- roughly half of new mothers experience “baby blues” excitement turns to irritability and crying. Lasts about 1-2w
- about 10-15% experience post-partum depression: irritability continues for months and is combined with feelings of low self-worth, poor appetite, and disturbed sleep
Preterm
Premature: babies born before 36 weeks
Low birth weight
- low <5.5 lbs
- very low <3.3lbs
- extremely low <2.2lbs
Cephalopelvic disporportion
?
Irregular position
Shoulder or breech
Preeclampsia
BP?
Prolapsed umbilical cord
Can cause hypoxia
Teratogens
Agents that cause abnormal prenatal development (drugs, disease, environmental hazards)
- dependent on dose, heredity, age
- prescription drugs: low brith weight
- illegal drugs: ?
- tobacco: poor ? Development
- alcohol: physical abnormalities
Teratogen facts
- the impact of teratogens chagnes during different times of prenatal development
- teratogens do not effect all body systems, different forms warrant different damages
- the greater th exposure, the greater the risk for damage
- not all damages associated with teratogens are evident and noticeable at birth
Maternal factors
- Nutrition: weight gain of mother (25-30lbs), folic acid, ?
- Stress: stress hormones cross placenta
- Rh factor: incompatibility can cause brith defects?
- Maternal age: increase age = increased risk of complications
Fetal ultrasound
Sound waves introduced via transducer converted into images
- determines fetus’ growth and presence of abnormalities
Amniocentesis
Amniotic fluid extracted. Identifies chromosomal or genetic abnormalities
CVS
?
Spinal bífida
Incomplete closure of neural tube early in pregnancy
Fetal alcohol syndrome
FAS_ fetal alcohol spectrum disorder
- slows physical growth
- leads to physical abnormalities, cardiac problems, decrease motor coordination, behavioral problems, and poor cognitive functioning
Smoking
- constricts blood vessels and reduces the oxygen and nutrients that can reach the fetus via placenta
- women that smoke are more likely to miscarry
- babies born from smoking mothers are more likely to have low brith weight
- second hand smoke can also cause babies to be smaller at birth
