Download prenatal dvlpt and birth

PRENATAL DVLPT AND BIRTH
GERMINAL/ZYGOTIC PERIOD
st
1 2 wks of pregnancy
about
of zygotes don’t make it thru this period; many times
mother doesn’t know she is pregnant
placenta: allows food and oxygen to reach zygote and allows waste products
to be carried away thru umbilical cord
umbilical cord: has 1 large vein that allows blood and nutrients to reach
zygote and 2 arteries that remove waste products
EMBRYONIC PERIOD
3-8 wks and now called an embryo
all organs and major systems are developed
EX:
by about 4 wks, about ¼” long and is in a curled up position
during the last part of the period,
can see buds that will become the
form
b/c of the many things forming, the embryo is now no longer curled up but in an
upright position
by 8th wk, is
long and weighs about
FETAL PERIOD
9 wks – birth and now called a fetus
organs, muscles, and nervous system become more organized and connected
can move arms, legs, head, and open and close mouth; can even suck its thumb
by end of 3rd mo., external genitals are formed and sex can be detected w/ ultrasound
other finishing touches by end of 3rd mo are
heartbeat can be heard also by end of 3rd mo
mother begins to feel movement anywhere b/t
mos.
, so roughly about 5
skin is protected from chapping while in amniotic fluid by vernix
vernix sticks to the skin w/ lanugo: white fine hair
most neurons are in place by end of
and very few will be produced after this;
all connections are not made just yet but they are still there
b/t
fetus has reached age of viability: able to survive with aid
if born before that, lungs are immature and brain is not able to control breathing and body
temp
gains most of its weight during the last
about
the last mo
gains more than 5 lbs and grows about 7 inches
need extra weight to
also receives antibodies from mom since immune system doesn’t work very well until a few
months after birth
PRENATAL ENVIRONMENTAL INFLUENCES
teratogens: any environmental agent that causes damage during the prenatal period
most susceptible and more damage done during
effects may not be immediate and can be subtle or delayed
prescription and nonprescription drugs:
aspirin: one of the most common over the counter drugs still used during pregnancy;
regular use can lead to low birth weight (less than 5 lbs), infant death around time of birth,
poor motor development and low intelligence scores in early childhood
caffeine: heavy intake (more than 3 cups a day) is associated with low birth weight,
miscarriage, and newborn withdrawal symptoms such as irritability and vomiting
illegal drugs:
cocaine and heroin: premature birth, low birth weight, physical defects, breathing
problems, and death around time of birth
most of them are born addicted if mom used regularly
crack: seem to be worse as far as their birth weight and damage done to central
nervous system
marijuana: linked to low birth weight and prematurity
tobacco:
about
of American women smoke during pregnancy
low birth weight, miscarriage, prematurity, spontaneous abortion (b/c of lack of
oxygen)
the more the mom smokes, the more the baby will be affected
if she stops at any time during pregnancy, those likelihoods decrease
even passive smokers are affected: low birth weight, infant death, and possible
problems with attention and learning
fetal alcohol syndrome:
mental retardation; impaired motor coordination, attention, memory, and language; also
overactivity
physical symptoms include widely spaced eyes, short eyelids, thin upper lip
interferes with brain development in early months of pregnancy and the alcohol pulls
away the oxygen the fetus needs to develop (cells don’t grow normally)
even small amounts are harmful, even less than one drink per day or 2 oz.
Other maternal factors
nutrition: if mother has healthy diet, should gain about 25-30 lbs during pregnancy
malnutrition can cause damage to central nervous system and can cause smaller
brain weight if during last 3 mos.
respiratory diseases because immune system is underdeveloped, low intelligence,
and learning problems
low income mothers usually have poorer nutrition
emotional stress: severe anxiety is associated with higher rates of miscarriage,
prematurity, low birth weight, respiratory illness, and digestive problems
during anxiety, fetus receives less oxygen and nutrients because the mother’s
blood flow has increased to other parts of her body
stress hormones also cross the placenta causing the fetus’s heart rate and
activity level to increase dramatically
stress weakens the immune system so mother is more susceptible to infectious
diseases
maternal age: women who wait until their thirties and forties are at a greater risk of
infertility, miscarriages, and babies born with chromosomal defects
young mothers (teens) can give birth to healthy baby but reasons for baby having
problems include mother not having access to prenatal care b/c may be from low income
family or may be afraid to seek prenatal care
prenatal care:
very important, especially if mother has health problems already
to ensure proper growth and development of fetus
of American women don’t get prenatal care until after 3 months
wait until end of pregnancy or don’t get the care at all
is usually the reason for not getting care
BIRTH
Stages of Labor
Stage 1: Dilation and thinning of cervix
longest stage; can last
if first birth and
hrs in later births
uterus contracts, causing the cervix to dilate and thin out; contractions get more
powerful and frequent
when cervix opens completely, birth canal if formed
Stage 2: Birth of the baby
for 1st and
in later births
mother begins to feel urge to push with her abdominal muscles
as mother pushes, baby is pushed down and out
Stage 3: Afterbirth
placenta will separate from the wall of the uterus and will come out within
minutes
Types of Childbirth
natural childbirth: designed to reduce pain and medical intervention; tries to make it as
rewarding an experience as possible for the parents
relaxation and breathing techniques to counteract the pain of contractions
home birth:
of American women choose home births
most are handled by certified nurse-midwives who have degrees in nursing and extra
training in childbirth management
Cesarean birth: surgically removing baby thru incision in abdomen
of births
usually done in medical emergencies: placenta separates from uterus too early; serious
maternal illness; infection
newborns can be sleepy and have breathing difficulties b/c anesthetic may have crossed
placenta
anoxia: inadequate oxygen supply during labor and delivery
can lead to cerebral palsy
breech position: butt or feet first around time of delivery or during delivery
can be turned early during delivery
analgesics and anesthetics:
of North American births use some type of medication
analgesics are mild doses used during labor to help mom relax
anesthetics are stronger and block sensation; i.e., an epidural
weaken uterine contractions in first stage of labor so interferes with mother’s ability
to feel contractions and push in 2nd stage of labor and then labor is prolonged
these do cross the placenta
Avg. length of pregnancy is
preterm: born several weeks before due date; considered preterm if before 36 wks;
can still be at appropriate weight, but just early
small-for-date: below expected weight when compared with length of pregnancy; can
be full-term and underweight
usually have more serious problems than preterm
more likely to die within 1st yr of life, catch infections, and have brain damage
possible causes: inadequate nutrition, placenta didn’t function normally, baby
already had defect
Avg. weight at birth:
avg. height at birth:
boys tend to be slightly longer and heavier than girls
The Newborn
Newborn’s appearance:
head is large compared with rest of body
head is cone-shaped from being in birth canal (if vaginal birth)
legs look short and bowed
large forehead and big eyes
Apgar scale: assesses infant’s physical condition at 1 and 5 minutes after birth
score from 0 (not present) to 2; 7 or better means infant is in good physical condition;
4-6 assistance with breathing and other vital signs; 3 or below serious danger and need
emergency medical attn
1. heart rate: needs to be 100-140 bts/min
2. respiratory effort: strong breathing and crying
3. reflex irritability (sneezing, coughing): strong reflexive response
4. muscle tone: strong movements of arms and legs
5. color: body, arms, and legs completely pink
Senses at birth
touch: well developed esp. around mouth, on the palms, and soles of feet; sensitive to pain
taste and smell: can show preferences for certain tastes, esp. sweets
will make certain facial expressions if sweet, sour, or bitter taste
certain odor preferences are innate; if unpleasant smell will turn head away to avoid
smell
know mother’s smell and prefer her smell, esp. if mother nurses
hearing: can hear wide variety of sounds but prefer complex sounds like noises and voices
are biologically prepared to respond to human voice
prefer speech that is high-pitched
vision: least developed at birth; visual structures in the eye and brain are not fully formed
yet
can’t focus very well and vision is very blurred
can see better if
away from object
Reflexes
rooting: touch cheek near corner of mouth and will turn head in that direction
disappears around
b/c can turn head voluntarily
sucking: if put finger in infant’s mouth, will begin sucking
by
it’s voluntary sucking
Moro: also called “startle” response; will arch back, extend legs, throw arms out and then
bring arms back in toward body
disappears around
Palmar grasp: put finger in infant’s palm and will grasp finger
disappears around
Babinski: stroke sole of foot from toe to heel and will fan out and curl up toes; disappears
withdrawal: stick sole of foot with pin and will pull foot away
weakens after
Sleep
spend about
a day sleeping
spend
of time in REM sleep; believe this is so brain can stimulate itself
and this is important for growth of CNS
Crying
1st way of communicating (if need food, comfort, etc.)
newborns usually cry b/c a physical need needs to be met, mainly hunger
also cry in response to temperature change when undressed, sudden noise, pain
can also cry at the sound of another baby crying
have different types of cry for different needs