1. 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

2. Conception and Implantation
Figure 3.1 Female reproductive organs, showing fertilization, early cell duplication, 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.)

8. Period of the Fetus Third month: Second trimester: Third trimester:
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

9. 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 Copyright © 2008, reprinted with permission from Elsevier, Inc.)
Figure 3.2 Sensitive periods in prenatal development

10. Teratogens Harm done by teratogens is affected by: dose heredity age
other negative influences
© Phil McDonald/Shutterstock 10

11. Teratogenic Substances
Drugs:
prescription
nonprescription
illegal
Tobacco
Alcohol
Radiation
Environmental pollution
Infectious disease
© Minerva Studio/Fotolia

12. Other Maternal Factors in Prenatal Development
Nutrition
Emotional stress
Rh factor incompatibility
Age
Lack of prenatal health care
© Dmitry Melnikov/Shutterstock

13. Importance of Prenatal Care
Monitor general health:
weight gain
capacity of uterus and cervix to support fetus
growth of the fetus
Treat complications:
diabetes
preeclampsia
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14. Stages of Childbirth Dilation and effacement of the cervix
Delivery of the baby
Delivery of the placenta
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15. Stages of Labor
Figure 3.4 A Normal Birth
Figure 3.4

16. The Baby’s Adaptation to Labor and Delivery
High levels of stress hormones
help baby withstand oxygen deprivation
prepare baby to breathe
arouse infant into alertness
© nattanan726/Shutterstock

17. The Apgar Scale Table 3.2 (Source: Apgar, 1953.)
Table 3.2 The Apgar Scale

18. Natural, or Prepared, Childbirth
Classes
Relaxation and breathing techniques
Labor coach: friend, relative, or trained doula
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19. Birth Complications Anoxia (oxygen deprivation) Breech position
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20. Medical Interventions in Childbirth
Fetal monitoring
Labor and delivery medication
analgesics
anesthetics
Cesarean delivery
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21. Preterm and Small-for-Date Infants
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

22. Interventions for Preterm Infants
Temperature-controlled isolette
Special stimulation:
gentle rocking
visual or auditory stimulation
touch, such as skin-to-skin kangaroo care
Parent training in infant caregiving
© Damon Yancy/Shutterstock

23. Infant Mortality in Thirty Nations
Figure 3.5 Infant mortality in thirty nations
Figure 3.5
(Adapted from U.S. Census Bureau, 2012.)

24. Newborn Reflexes
Rooting
Sucking
Moro
Stepping
© philipus/Fotalia

25. Infant States of Arousal
Rapid-eye-movement (REM) sleep
Non-rapid-eye-movement (NREM) sleep
Drowsiness
Quiet alertness
Waking activity and crying
© Vasilyev Alexandr/Shutterstock

28. Soothing a Crying Baby Hold on shoulder, rock or walk Swaddle
Offer pacifier
Massage baby’s body
Talk softly or play rhythmic sounds
Combine methods
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29. Newborn Sense of Touch Sensitive to touch
around mouth
on palms and soles of feet
Use touch to investigate their world
Severe pain
overwhelms nervous system with stress hormones
can be relieved with local anesthesia, sugar solution, or physical touch
© Eleonora_os/Shutterstock

30. 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

31. Newborn Sense of Hearing
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

32. Newborn Sense of Vision
Least developed sense at birth
Limited visual acuity
Actively explore environment:
scan for interesting sights
track moving objects
Not yet good at discriminating colors
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33. New Family Adjustment Hormones that facilitate caregiving:
oxytocin
prolactin
estrogens
Hormonal effects may depend on experience
Challenges of early weeks:
new roles
changed schedule
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