CH 4: Prenatal Development and Birth Flashcards
(108 cards)
1
Q
Prenatal development
A
the changes that transform the fertilized egg into a newborn human
2
Q
How long does prenatal gestation take and how much can it vary by?
A
38 weeks; up to 37 days/5 weeks
3
Q
3 stages of prenatal development & their length
A
- period of the zygote - weeks 1-2
- period of the embryo - weeks 3-8
- period of the fetus - weeks 9-38
4
Q
When does fertilization end?
A
When the zygote implants itself in the wall of the uterus
5
Q
How often does cell division occur in a zygote?
A
every 12 hours
6
Q
first stage of the period of the zygote
A
fertilization
7
Q
implantation & how long it takes to complete
A
burying of the zygote into the uterine wall; about a week
8
Q
how large is an implanted zygote?
A
diameter less than 1 mm
9
Q
germ disc
A
small cluster of cells near the center of the zygote that will eventually turn into a baby
10
Q
role of the placenta
A
exchange nutrients and wastes between mother and baby
11
Q
what marks the end of the period of the zygote?
A
implantation and cell differentiation
12
Q
embryo
A
a zygote completely embedded into the uterine wall
13
Q
3 layers of the embryo
A
ectoderm
mesoderm
endoderm
14
Q
ectoderm
A
outer layer of the embryo that becomes hair, outer skin & NS
15
Q
mesoderm
A
middle layer of the embryo that will become muscles, bones and the circulatory system
16
Q
endoderm
A
inner layer of the embryo that will become the digestive system and the lungs
17
Q
3 week old embryo vs 8 week old embryo
A
3wk old: about 2 mm long & looks like a salamander
8wk old: about 2cm long can see eyes and limbs, heart has been beating for around a month, brain and NS are rapidly developing, too small for mother to physically feel
18
Q
amniotic sac
A
sac where the embryo rests
19
Q
2 things that link embryo to mother
A
umbilical cord and placenta
20
Q
umbilical cord
A
contains the blood vessels that join the embryo to the placenta
21
Q
villi
A
projections from the umbilical cord vessels that blood flows through; lie close to the mother’s blood vessels and allows for nutrients/waste products/oxygen to be exchanged b/w mother and embryo
22
Q
2 embryo growth principles
A
cephalocaudal principle & proximodistal principle
23
Q
cephalocaudal principle
A
the head develops before the rest of the body followed by arms and legs developing before hands and feet (top-down)
24
Q
proximodistal principle
A
the center of the body grow before more distant parts (center-out)
25
when can most mothers feel the fetus move?
around 4 weeks/when fetus weighs 100-225 grams
26
how much weight does the fetus gain in the final 5 months?
3-3.6 kg
27
what finishing touches are put on the fetus during the fetal period?
nervous, respiratory and digestive systems
28
what regions of the brain grow during the fetal period?
all; particularly the cerebral cortex
29
when are testicles and ovaries developed?
near the end of the embryonic period
30
when is the sex hormone to make the fetus a male secreted/not secreted?
third month
31
vernix
thick substance that protects the fetus while in the amniotic sac
32
age of viability
age when most bodily systems function well enough to support life once the baby is born (22-28wks)
33
when does the developing child begin to emit behavior?
gestation
34
The Cat in the Hat example from prenatal development
Expectant mothers read aloud the cat in the hat to their fetuses and when the babies were born they sucked on a nipple to get their mother to read the cat in the hat but stopped when they started reading other stories
35
main takeaways from each period
zygote: egg is fertilized and zygote implants itself in wall of uterus
embryo: period of rapid growth and most body structures begin to form
fetus: huge increase in size and most body systems begin to work
36
5 steps towards a healthy baby
1. visit a health-care professional for regular checkups
2. professional might recommend diet supplements
3. no alcohol or cigarettes and limit caffeine
4. exercise throughout pregnancy
5. get plenty of rest
37
most pregnant women need to increase their caloric intake by how much?
10-20%
38
what is the normal weight women weight gain at 40wks of pregnancy? and how does it al balance out?
13.9kg; 1/3 is the baby and the placenta; 1/3 is the increase in the mother's fat; 1/3 is the increased volume of blood and breast/uterus size
39
when mothers do not consume enough of this, their babies are at risk for neural tube defects
folic acid
40
spina bifida
disorder in which the embryo's neural tube doesn't close properly
41
inadequate nourishment can impact the baby mainly how?
can impact the baby's NS
42
why are there only correlational studies regarding pregnant mothers and stress?
it is unethical to subject anyone to extreme stressful situations
43
women who report higher stress levels during pregnancy typically what?
give birth early and have underweight babies
44
what are traditionally considered the prime childbearing years?
20s
45
what's the suggested optimal age for having a child?
25-34
46
children of younger vs older mothers tended to be affected by what?
younger: infectious diseases
older: mental disorders, heart disease and circulatory disease
47
teenage pregnancy tends to be associated with what?
pre-term deliveries and low birth weight
48
main 3 general pregnancy risk factors
nutrition
stress
mother's age
49
teratogen
agent that disrupts normal prenatal development
50
what drug was introduced to Canada and Germany in the 1950s to help pregnant women sleep better and control nausea but resulted in babies with birth defects?
thalidomide
51
5 most common teratogenic diseases
AIDS
cytomegalovirus
genital herpes
rubella
syphilis
52
consequences for developing baby from a mother with AIDS
frequent infection, neuro disorder and death
53
consequences for developing baby from a mother with cytomegalovirus
deafness, blindness, abnormally small head, cognitive delay
54
consequences for developing baby from a mother with genital herpes
encephalitis, enlarged spleen, improper blood clotting
55
consequences for developing baby from a mother with rubella
cognitive delay, damage to eyes, ears and heart
56
consequences for developing baby from a mother with syphilis
damage to CNS, teeth and bones
57
which diseases attack the baby through the placenta; at birth; or both
cytomegalovirus, rubella, syphilis; genital herpes; AIDS
58
5 common teratogenic drugs and their consequences
Alcohol: fetal alcohol spectrum disorder, cognitive deficits, heart damage and retarded growth
Caffeine: lower birth weight & decreased muscle tone
Marijuana: low birth weight & less motor control
Nicotine: retarded growth and possible cognitive impairments
Aspirin: deficits in intelligence, attention and motor skills
59
Doing this before pregnancy can result in lowered rates of fertility, infertility, and implantation in the fallopian tube
Smoking
60
Smoking during pregnancy can cause what?
Problems with the placenta, low birth weight, preterm birth, cleft palate and sudden infant death syndrome
61
main 2 points of FASD
children grow slower than normal and have heart problems
62
environmental teratogens and their effects on the baby
lead- cognitive delay
mercury- retarded growth, cognitive delay, cerebral palsy
polychlorinated biphenyls- impaired memory and verbal skills
x-rays- retarded growth, leukemia and cognitive delay
63
from what can PCBs contaminate animals and fish?
seeping into groundwater
64
pregnant women should try to do what to stay careful of the food they eat and air they breathe?
clean foods thoroughly to rid insecticides
avoid foods with chemical additives
stay away from air contaminated by household products
stay away from cats and litter boxes (toxoplasmosis)
65
4 main principles of teratogenic effect
1. the impact of a teratogen depends upon the child's genotype
2. the timing of exposure to a teratogen plays a huge role
3. teratogen harm is selective and each one affects a specific aspect of prenatal development
4. damage from teratogens may not be evident at birth but can appear later in life
66
when can ultrasound photos determine the gender of the baby?
16-20 wks after conception
67
amniocentesis
a needle is inserted in the mother's abdomen to obtain a sample of the amniotic fluid
68
chorionic villus sampling
a small tube is inserted into the uterus through the vagina to collect cells from the placenta
69
when are amniocentesis and chorionic villus sampling used?
when a genetic disorder is suspected
70
fetal surgery can be done how?
endoscopically or openly
71
how long after conception does a women typically go into labour?
38 weeks
72
cervix
opening at the end of the uterus that is the entryway to the birth canal
73
steps of stage 1 of child labour
-contractions are weak and irregular; cervix is 5cm dilated
-contractions are stronger and at regular intervals; cervix is 7-8cm dilated
-contractions are intense and can occur nonstop; cervix is 10cm dilated
74
what is apparently the most painful part of child labour?
the transition phase at the end of stage 1
75
how long does stage 1 of child labour typically last?
12-24 hrs
76
steps of stage 2 of child labour
-women get the urge to push the baby out with their abs
-baby is propelled down the birth canal with help from contractions and abdomen
-crowning
-baby's birth
77
crowning
when the top of the baby's head appears during labour
78
breech presentation
when the developing baby's feet are facing the birth canal instead of the head
79
steps of stage 3 of child labour
-placenta is expelled from the uterus
-only lasts 10-15 mins
80
doula
a professional who provides support and education about childbirth but does not intervene medically
81
Caesarean section
baby is removed from the uterus by an incision in the mother's abdomen
82
midwife
a non-physician who is trained to help mothers with natural vaginal delivery
83
why are natural methods of dealing with birthing pain emphasized over medication>
medication prevents women from using their ab muscles to push the baby through the birth canal
84
3 strategies offered in childbirth classes for women to counteract pain without drugs
deep breathing
visual imagery
a support coach
85
2 forms of lacking oxygen
anoxia: complete deprivation
hypoxia: reduced oxygen supply
86
when might a doctor want to do a C section?
when the fetus is in distress
87
one of the greatest challenges for preemie babies?
damage/underdevelopment of the cerebellum
88
prematurity vs small for date babies
premature: babies born earlier than full term
small for date: babies born at a lighter weight than expected for whenever they were born
89
small-for-date babies are often born from mothers that what?
smoked and drank during pregnancy
90
babies who weigh less than how much often don't survive at birth?
1500g
91
small for date babies weighing more than 1500grams have better chances of survival but still may experience what?
lower developmental level than others
92
what turns out to be one huge factor for at-risk newborns as they develop?
environmental factors
93
"development proceeds best when women receive ________ and _________"
good prenatal care; children live in a supportive environment
94
Apgar score
measured used to evaluate a newborn's vital signs
95
5 vital signs of a newborn
breathing
heartbeat
muscle tone
presence of reflexes
skin tone
96
5 measures on the Apgar scale
activity
pulse
grimace
appearance
respiration
97
an Apgar score of what indicates a baby in good condition?
7 or higher
98
a score of what on the Apgar test indicates a life threatening situation for the baby?
3 or lower
99
newborns spend most of their alternating between what 4 states?
alert inactivity (calm baby)
waking activity (uncoordinated and unfocused)
sleeping
crying
100
3 types of baby cries
basic
mad
pain
101
how often do newborns sleep daily?
16-18hrs
102
sleep-wake cycle of newborns
sleep for 3 hours;awake for 1 hour
103
roughly half of newborns sleep is what kind?
REM sleep
104
sudden infant death syndrome
a healthy baby dies suddenly for no apparent reason
105
when is SIDS more likely?
preemies/small-for-date babies
parents smoke cigs
baby sleeps face down
during the winter
106
postpartum depression
low self worth, disturbed sleep and poor appetite that 10-15% of new mothers feel for months after birth
107
children of mothers who suffer from PPD for months on end are at higher risk for what?
having depression themselves and other behavior problems
108
how many centres in the world do fetal surgery?
2
