1. Infants, Children, and Adolescents
Eighth Edition
Chapter 3
Prenatal Development

2. Learning Objectives (1 of 2)
3.1 How has decision making about childbearing changed over the past half century, and what are the consequences for child rearing and child development?
3.2 List the three phases of prenatal development, and describe the major milestones of each.
3.3 What are teratogens, and what factors influence their impact?
3.4 List agents known to be or suspected of being teratogens, and discuss evidence supporting their harmful impact.

3. Learning Objectives (2 of 2)
3.5 Describe the impact of other maternal factors on prenatal development.
3.6 Why is early and regular health care vital during the prenatal period?
3.7 What factors contribute to preparation for parenthood during the prenatal period?

4. Why Have Children?
In Western nations, having children is a matter of individual choice.
90% of U.S. adults have or plan to have children, depending on:
Financial circumstances
Career goals
Values
Health conditions

5. Why Have Children? (continued)
Advantages:
Personal fulfillment
Being a responsible and mature adult
Caregiving and support in old age
Continuing the family name
Strengthening couple relationship

6. Why Have Children? (continued)
Disadvantages:
Responsibility for child’s well-being
Role overload
Financial strain
Loss of privacy

7. How Large a Family?
Average number of children has declined in Western nations since 1960
More effective birth control
Fewer children more compatible with women’s careers
Divorce
Low-SES mothers tend to have more children

8. American Mothers Getting Older
Advantages:
More emotionally mature
Financial stability
Disadvantages:
Declining reproductive capacity (female and male)
Increased risk of chromosomal and genetic disorders

9. American Women Bearing Children at Older Ages
Figure 3.1: First births to American women of different ages in 1970 and 2008
Figure 3.1
(Based on U.S. Census Bureau, 2014b.)

10. Conception and Implantation
Figure 3.2: Female reproductive organs, showing fertilization, early cell duplication, and implantation
Figure 3.2
(From Before We Are Born, 6th ed., by K. L. Moore and T. V. N. Persaud, p. 87. Copyright © 2003, reprinted with permission from Elsevier, Inc.)

11. Periods of Prenatal Development
Germinal
Embryonic
Fetal

12. Germinal Period Weeks 1–2 Implantation of the blastocyst
Development of the
Amnion
Chorion
Placenta
Umbilical cord

13. The Placenta and Umbilical Cord
Figure 3.3: cross-section of the uterus, showing detail of the placenta
Figure 3.3
(From Before We Are Born, 6th ed., by K. L. Moore and T. V. N. Persaud, p. 95. Copyright © 2003, reprinted with permission from Elsevier, Inc.)

14. Embryonic Period Weeks 3–8
Central nervous system, internal organs, muscles, and skeleton begin to form.
Heart begins pumping blood.
Liver and spleen begin producing blood cells.
Neurons develop rapidly.
External features also form: eyes, ears, nose, limbs.
Testes in male begin producing testosterone

15. Fetal Period Week 9 to the end of pregnancy First trimester:
Organs, muscles, and nervous system organize.
External genitals are well-formed.
Second trimester:
Mother can feel movements.
Neurons form synapses at a rapid pace.
Sensitivity to sound and light emerges.

16. Fetal Period (continued)
Third trimester:
Fetus reaches age of viability (between 22 and 26 weeks).
Rapid gain in neural connectivity and organization continue.
Responsiveness to external stimulation increases.
Extensive body growth occurs.

17. Prenatal Environment and Later Health
Low Birth Weight
Greater chance of
Heart Disease
Stroke
Diabetes
High Birth Weight
Breast cancer
Prostate and other cancers

18. Prenatal Environmental Influences: Teratogens
Any environmental agent that causes damage during the prenatal period
Effects depend on:
Dose
Heredity
Other negative influences
Age

19. Teratogens Drugs Tobacco Alcohol Radiation Pollution
Prescription
Nonprescription
Illegal
Tobacco
Alcohol
Radiation
Pollution
Infectious disease

20. Drugs Prescription and nonprescription
Isotretinoin: eye, ear, skull, brain, heart, and immune system abnormalities
Aspirin: possible low birth weight, infant death, poor motor development, lower intelligence
Caffeine: low birth weight
Antidepressants: premature delivery, birth complications, high blood pressure

21. Drugs (continued) Illegal drugs
Cocaine, heroin, and methadone are all linked to a variety of severe problems.
Marijuana is associated with poor academic achievement, impulsivity, depression.
Lasting findings, however, are not well established.

22. Tobacco 11% of U.S. women smoke while pregnant. Can cause:
Low birth weight
Miscarriage
Prematurity
Cleft lip and palate
Abnormal blood vessels
Infant death
Asthma and cancer later in childhood

23. Fetal Alcohol Spectrum Disorder: Criteria for Diagnosis
DIAGNOSTIC CATEGORY
Criteria
FAS
p-FAS
ARND
Slow physical growth
Yes No
Facial abnormalities:
Short eyelid openings
Thin upper lip
Smooth or flattened philtrum
All three are present
Two of the three are present
None are present
Brain injury
Impairment in a minimum of three areas of functioning
Table 3.3
Source: Mattson, Crocker, & Nguyen, 2012.

24. The Effects of Environmental Pollution
More than 75,000 chemicals are in common use in the United States.
Many babies are “born polluted”
Diverse impairments in physical and mental development
Increased chances of life-threatening diseases and later health problems

25. Infectious Disease Viruses Bacteria and Parasites Rubella Chickenpox
HIV and AIDS
Various herpes viruses
Bacteria and Parasites
Toxoplasmosis
Chlamydia and syphilis
Tuberculosis

26. Maternal Factors in Prenatal Development
Exercise
Nutrition
Emotional stress
Rh blood factor
Maternal age
Previous births

27. The Effects of Emotional Stress on the Developing Fetus
Stress hormones cross the placenta, causing a dramatic rise in fetal heart rate and activity.
Maternal emotional stress predicts anxiety, short attention span, anger, aggression, and overactivity among young children.
Stress-related prenatal complications can be greatly reduced when mothers receive support from family members and friends.

28. The Nurse–Family Partnership
Voluntary home visiting program for low-income, first-time mothers
Children having experienced the program show:
Higher language and intelligence scores
Fewer behavior problems
Mothers in the programs experience:
Fewer subsequent births, greater birth spacing
More contact with child’s father
More stable intimate relationships
Less welfare dependence

29. Prenatal/Birth Complications Increase with Maternal Age
Figure 3.6: Relationship of maternal age to prenatal and birth complications
Figure 3.6
(Based on Salihu et al., 2003.)

30. Iron Deficiency and Memory Impairments in Infants of Diabetic Mothers
Throughout pregnancy, mother’s volatile glucose levels can cause birth defects or abnormal fetal growth.
The fetus’s reaction to this extra glucose results in iron deficiency, which harms brain cell growth.
Resulting memory problems continue into the preschool years.

31. Expectant Mothers with Late or No Prenatal Care
Figure 3.7: Expectant mothers in the United States with late (after the first trimester) or no prenatal care
Figure 3.7
(Based on Child Trends, 2014b.)

32. Reasons Women Delay Prenatal Care
Financial hardship
Situational barriers
Personal barriers
Many are reluctant to disclose high-risk behaviors

33. Culturally Sensitive Prenatal Care Promotes Healthy Pregnancies
Low-SES ethnic minority women often reported depersonalizing prenatal care.
Group prenatal care offers a sensitive alternative
group discussions about health issues in native language
led to more health-promoting behaviors and reduced low birth weight and prematurity

34. Preparing for Parenthood
Expectant parents
get to know the baby as an individual.
look for models of effective parenthood.
adjust their relationship as a couple.

35. Readers may view, browse, and/or download material for temporary copying purposes only, provided these uses are for noncommercial personal purposes. Except as provided by law, this material may not be further reproduced, distributed, transmitted, modified, adapted, performed, displayed, published, or sold in whole or in part, without prior written permission from the publisher.