Psychology 262 Natalie B. Phelps M.S. Ed. NCC Chapter 3 Prenatal Development

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Psychology 262 Natalie B. Phelps M.S. Ed. NCC
Chapter 3Prenatal Development
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Prenatal Development

• 1. Describe what it means to say that the most
  rapid and dramatic human developments are 'out of
  sight' or occur before birth.
• 2. Explain why a newly fertilized egg cell must
  survive for more than a week without nourishment
  from the mother.
• 3. Discuss how early the heart starts beating.
  How large is the embryo when the heart starts
  beating?
• 4. Discuss what you know about the proportion of
  conception of females versus males.
• 5. Explain what kind of movements and fetal
  actions may occur during the fetal stage of
  development.

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Prenatal DevelopmentContinued

• 6. Why do some parents play classical music and
  point the speakers toward their abdomens during
  pregnancy?
• 7. Is it true that embryos and fetuses take what
  they need from their mothers? Why or why not? Do
  pregnant women need to be concerned about their
  diets? Why or why not?
• 8. What disease-causing germs can cross the
  placental barrier and infect the embryo and
  fetus?
• 9. Is it safe for a pregnant woman to have a
  couple of glasses of wine in the evening? Why or
  why not? Is it safe for a pregnant woman to
  smoke? Why or why not?
• 10. What is the ideal age for carrying and
  bearing a child?

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Without Food

• A newly fertilized egg cell must survive for more
  than a week without nourishment from the mother.
  Until the fetuse reaches the uterus and attach to
  the uterine wall.

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Prenatal Development Is Divided Into Three Stages

• The earliest stage, called the germinal stage.
• The second stage of prenatal development is
  called the embryonic stage.
• The third stage of prenatal development is
  referred to as the fetal stage.

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The Germinal Stage (p. 79)

• The earliest stage, called the germinal stage,
  (lasts two weeks after conception.)
• The fertilized egg cell travels to the uterus and
  attaches to the uterine wall.
• The key features of this stage are a rapid
  dividing of cells, the beginning of cell
  differentiation, and the development of the
  umbilical cord and the placenta.
• The umbilical cord (Food and Waste) will serve as
  a pathway for nutrients to be passed from the
  mother to the developing child and for wastes to
  be transferred from the developing child to the
  mother for disposal.
• The placenta (harmful chemicals and viruses)
  serves as a filtration system that will keep many
  (but not all) harmful chemicals and viruses from
  being transferred from the mother to the child.

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The Embryonic Stage (p.81-83)

• The second stage of prenatal development is
  called the embryonic stage, which lasts from the
  implantation of the zygote to the uterine wall
  until the eighth week of development.
• Key features of this stage of development
  include
• (1) development of the nervous system
• (2) development of key organs such as the
  pancreas and liver
• (3) development of the circulatory systems
• (4) sexual differentiation

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The Fetal Stage

• The third stage of prenatal development is
  referred to as the fetal stage. This period lasts
  from about the eighth week after conception until
  birth.
• During this stage, the developing child will
  begin moving and responding to external
  stimulation.
• In addition, this period is marked by rapid and
  substantial growth of the developing child.
• DeCasper Fife (1980) have shown that the fetus
  responds to external stimulation, can hear, and
  that newborns show preferences for things they
  have heard while in the uterus.
• This amazing discovery suggests that children
  can, at some level, remember what they heard
  while in utero.

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Three Trimesters

• p. 88-89
• First Trimester
• Period of the Ovum (Germinal Stage)
• First 2 weeks
• Embryonic Stage
• Weeks 3 to 8
• Fetal Stage
• Weeks 9 to birth
• Second Trimester
• Weeks 13 to 16
• Weeks 17 to 20
• Weeks 21 to 24
• Third Trimester
• Weeks 25 to 28
• Weeks 29 to 36-38

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Environmental Influences

• During all stages of prenatal development, the
  developing child is vulnerable to the effects of
  external agents, called teratogens, such as
  drugs, alcohol, or environmental pollutants.
• The effect these agents may have on the
  developing child depends on
• (1) the extent of the exposure
• (2) the type of agent
• (3) the time period in which the developing child
  is exposed to the agent
• The best advice, of course, is to avoid as many
  of these agents as possible for the duration of
  the pregnancy

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Critical Periods

• p. 93
• Teratogens
• Environmental influences or agents that can
  damage the embryo or fetus (from the Greek teras,
  meaning monster).
• Knowledge of the sequences of prenatal
  development allows one to understand why specific
  teratogens are most harmful during certain
  periods of prenatal development.

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Other Environmental Influences

• Nutrition
• Research shows that malnutrition in the mother
  can have serious and, sometimes, potentially
  long-term effects on the child.
• Obese mothers have a higher risk of stillbirth.
• Overly slender mothers run the risk of having a
  premature baby.
• Teratogens do not just include environmental
  influences or items that the mother ingests.
• They can also be produced by the mother's own
  body.
• Rh incompatibility, for example, is an illness
  that results when the mother produces Rh-positive
  antibodies (because she is Rh-negative) and is
  carrying an Rh-positive fetus.
• The resulting incompatibility can cause anemia,
  mental deficiencies or even death to the fetus.

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Other Environmental InfluencesContinued

• Another example is HIV.
• It is not known how HIV crosses the placenta and,
  in many cases, why it does not, but the disease
  can create significant problems for the unborn
  child. The placenta filters many impurities
  including those that might otherwise be
  transferred from the mother.

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Agents Risks

• p. 102-103
• Prescription Drugs
• Other Drugs
• Vitamins
• Pathogens (disease-causing agents)
• Environment Hazards
• Bio-chemical Incompatibility with Mother

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Too much or too little of things can be dangerous
to the developing child

• To Much Vitamins Are Not Good Either
• Vitamins are a good thing and are especially
  important if the mother's nutrition is otherwise
  poor. At the same time, excessive intake of
  vitamins (such as A and D), have been associated
  with central nervous system damage.
• Marijuana and cocaine have also been shown to
  have negative effects on children.
• Marijuana use during pregnancy, for example, is
  associated with attention deficits (ADD) in
  children.
• Cocaine use during pregnancy is related to
  hyperactivity and attention (ADHD) problems as
  well.

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Fetal Alcohol Syndrome (FAS)

• This syndrome is characterized by distinct facial
  features (such as widely spaced eyes, a flattened
  nose, and underdeveloped jaw).
• It is uncertain how much alcohol will lead to
  this disorder so, again, the best advice for
  anyone who is pregnant or might become pregnant
  is to avoid alcohol consumption.
• In addition, FAS is associated with a variety of
  cognitive impairments as well as with problems in
  coordination and in the cardiovascular system.
• Research shows that alcohol and drug consumption
  on the part of the father can also affect the
  conceived child.
• Part of this effect may be due to the fact that
  ingestion of some chemicals can cause deformities
  in the sperm of the father. Additionally, this
  appears to be true for men who smoke.

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Is it safe for a pregnant woman to smoke?

• No. There is a more direct (research wise)
  relationship between smoking and the development
  of the child.
• Smoking, of course, affects the mother's lungs.
  At the same time, that oxygen deprivation will
  impact the developing child.
• Babies born to mothers who smoke tend to be
  smaller, more often are stillborn, and, as
  children, more likely to have behavioral and
  cognitive problems.

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What is the ideal age for carrying and bearing a
child?

• From a biological standpoint, the 20's may be the
  ideal age for bearing children.
• Women who are younger have a higher incidence of
  infant mortality and low birth weight while older
  mothers (over age 30) have a greater risk of
  having a child with Down's Syndrome.

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Stress

• Stress on the mother can effects the fetus.

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Exercise 1

• p. 32 (SG-CA book)
• You are running a clinic for expectant mothers in
  a very poor neighborhood. One of the mothers has
  asked for your advice on what she can do to
  increase her chances of having a healthy baby.
  She cannot afford to eat a very good diet. Given
  this information, and based on what you have
  learned in this chapter, what advice would you
  give her? Be sure and include information from
  the chapter to support your advice.

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Pamphlet for Expectant MothersTwo groups

• (OW-CA book) p. 5
• First-time expectant mothers are often bombarded
  with information about what they should do or not
  do during their pregnancy. In this project you
  are going to compile a short and concise pamphlet
  for expectant mothers. In this pamphlet you are
  to include information regarding prenatal care
  including nutrition and exercise. You are also to
  address the issue of common teratogens and the
  prevention of birth defects. This should only be
  a two-page pamphlet so you must decide on what
  would be the most critical information for
  expectant mothers to have. Include at least five
  points regarding nutrition and three points
  regarding exercise. Also include general
  information regarding teratogens, eight common
  teratogens and advice regarding how to avoid
  exposure. Attach your pamphlet below. Be
  creative!

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The End!