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Exploring Lifespan Development Third Edition Laura E. Berk
Chapter 3
Prenatal Development, Birth,
and the Newborn Baby
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Conception and Implantation
Figure 3.1
(From Before We Are
Born, 6th ed., by K.L.
Moore & T.V.N. Persaud,
p. 87. Copyright © 2003,
reprinted with permission
from Elsevier, Inc.)
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Periods of Prenatal
Development
Period and Length
Key Events
Zygote
(2 weeks)
Fertilization
Implantation
Start of placenta
Embryo
(6 weeks)
Groundwork laid for all body
structures and internal organs
Fetus
(30 weeks)
“Growth and finishing” phase
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Formation of the Zygote
• The zygote begins when the ovum is penetrated
by a sperm. Over the next 30 hours, it divides
once, and then divides more rapidly over the
next two weeks.
• The cells on the inside of this ball will become
the organism; the cells on the outside will
become the placenta and supporting structures.
• By the fourth day, 60 or 70 cells form a hollow,
fluid-filled blastocyst.
• Sometime between the 7th and 9th day, the
blastocyst burrows into the uterine wall.
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Period of the Zygote/Germinal
Period
• The first two weeks after fertilization
• Includes formation of the zygote
• The zygote splits to form a blastocyst, and
then the hollow, fluid-filled blastula.
• The blastula travels to the uterus and
implants
• Cell differentiation, producing the
embryonic disc and supporting structures,
begins by the end of the first week.
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Period of the Embryo
• End of the 2nd week until the end of the second month
after fertilization; when fertilization is complete.
• Outer cells of the blastula produce supporting structures;
inner cells of the inner, embryonic disc differentiate into
the embryo itself.
• Three structures are produced: amniotic sac: a
membrane filled with amniotic fluid, which helps
cushion and protect the embryo; the placenta; mass of
tissue attached to the uterine wall that acts as a filter;
umbilical cord: connects placenta to the embryo,
contains 2 fetal arteries and one fetal vein.
• First 6 weeks: the embryo develops arms, legs, fingers,
toes, a face, a beating heart, a brain, lungs, and all other
major organs
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
The Embryo
• After implantation, the embryo develops into three
distinct layers:
• Ectoderm: becomes the nervous system and skin
• Mesoderm: becomes the muscles, skeleton,
circulatory system, and other internal organs
• Endoderm: becomes the digestive system, lungs,
urinary tract, and glands
• The ectoderm folds over to form the neural tube that will
become the spinal cord and brain.
• Arms and legs unfold, eyes become visible and lungs,
digestive and excretory systems begin to form.
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Period of the Fetus
Third month:
organs, muscles, and nervous system start to
become organized and connected
lungs begin to expand and contract
Second trimester:
many organs are well-developed by 20 weeks
most of the brain’s neurons are in place
Third trimester:
age of viability: 22–26 weeks
fetus takes on beginnings of personality
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Sensitive Periods in
Prenatal Development
Figure 3.2
(Adapted from
Before We Are
Born, 7th ed., by
K.L. Moore &
T.V.N. Persaud,
p. 313. Copyright
© 2008, reprinted
with permission
from Elsevier,
Inc.)
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Teratogens
Harm done by teratogens
is affected by:
dose
heredity
age
other negative influences
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Exploring Lifespan Development Third Edition Laura E. Berk
Teratogenic Substances
Drugs:
prescription
nonprescription
illegal
Tobacco
Alcohol
Radiation
Environmental pollution
Infectious disease
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Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Other Maternal Factors in
Prenatal Development
Nutrition
Emotional stress
Rh factor
incompatibility
Age
Lack of prenatal health care
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Exploring Lifespan Development Third Edition Laura E. Berk
Importance of Prenatal Care
Monitor general health:
weight gain
capacity of uterus and
cervix to support fetus
growth of the fetus
Treat complications:
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diabetes
Preeclampsia:
Tomexmia – affects 510% of women
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Stages of Childbirth
Dilation and
effacement of
the cervix
Delivery of
the baby
Delivery of the
placenta
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Exploring Lifespan Development Third Edition Laura E. Berk
Stages of Labor
Figure 3.4
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
The Baby’s Adaptation
to Labor and Delivery
High levels of stress
hormones
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help baby withstand
oxygen deprivation
prepare baby
to breathe
arouse infant into
alertness
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Exploring Lifespan Development Third Edition Laura E. Berk
The Apgar Scale
Table 3.2
(Source: Apgar, 1953.)
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Exploring Lifespan Development Third Edition Laura E. Berk
Natural, or Prepared,
Childbirth
Classes
Relaxation and
breathing techniques
Labor coach: friend,
relative, or trained
doula
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Exploring Lifespan Development Third Edition Laura E. Berk
Birth Complications
Anoxia (oxygen deprivation)
Breech position
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Exploring Lifespan Development Third Edition Laura E. Berk
Medical Interventions
in Childbirth
Fetal monitoring
Labor and delivery
medication
analgesics
anesthetics
Cesarean delivery
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Exploring Lifespan Development Third Edition Laura E. Berk
Preterm and
Small-for-Date Infants
Preterm
Born several weeks
or more before their
due date
Weight may be
appropriate for
length of pregnancy
Small-for-Date
May be either
preterm or
full-term
Below expected
weight for length
of pregnancy
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Interventions for
Preterm Infants
Temperature-controlled
isolette
Special stimulation:
gentle rocking
visual or auditory stimulation
touch, such as skin-to-skin kangaroo care
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Parent training in infant caregiving
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Exploring Lifespan Development Third Edition Laura E. Berk
Infant
Mortality
in Thirty
Nations
Figure 3.5
(Adapted from U.S. Census Bureau, 2012.)
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Exploring Lifespan Development Third Edition Laura E. Berk
Newborn Reflexes
Rooting
Sucking
Moro
Stepping
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Exploring Lifespan Development Third Edition Laura E. Berk
Newborn Sense of Touch
Sensitive to touch
around mouth
on palms and soles of feet
Use touch to investigate
their world
Severe pain
© Eleonora_os/Shutterstock
overwhelms nervous system with stress
hormones
can be relieved with local anesthesia, sugar
solution, or physical touch
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Exploring Lifespan Development Third Edition Laura E. Berk
Newborn Senses of
Taste and Smell
Infants
have a preference for sweet tastes
at birth
can readily learn to like new tastes
have odor preferences at birth
can locate odors and identify mother
by smell from birth
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Newborn Sense of Hearing
Newborns
can hear a wide variety of sounds
prefer complex sounds to pure tones
can distinguish between a variety of sound
patterns when only a few days old
listen longer to human speech than to
nonspeech sounds
can detect the sounds of any human
language
Copyright © 2014, 2011, 2008 by Pearson Education, Inc. All Rights Reserved.
Exploring Lifespan Development Third Edition Laura E. Berk
Newborn Sense of Vision
Least developed sense at birth (20/600)
Limited visual acuity
Actively explore environment:
scan for interesting sights
track moving objects
Not yet good at
discriminating colors
Adult-like color vision at 4mos
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