• Chapter 3 – Prenatal Development, Birth, and the Newborn Baby

Periods of Prenatal Development

• 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

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

Teratogens

• Harm done by teratogens is affected by:
  • dose
  • heredity
  • age
  • other negative influences
• Teratogenic Substances
  • Drugs:
    • prescription
    • nonprescription
    • illegal
  •  Tobacco
  •  Alcohol
  • Radiation
  • Environmental pollution
  • Infectious disease
• Other Maternal Factors in Prenatal Development
  • Nutrition
  • Emotional stress
  • Rh factor incompatibility
  • Age
  • Lack of prenatal health care

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

Stages of Childbirth

• Dilation and effacement of the cervix
• Delivery of the baby
• Delivery of the placenta

Stages of Labor

• Stage 1
  • Dilation and Effacement of the Cervix
    • Contractions of the uterus cause dilation and effacement of the cervix
  • Transition
    • Transition is reached when the frequency and strength of the contractions are at their peak and the cervix opens completely
• Stage 2
  • Pushing
    • With each contraction, the mother pushes, forcing the baby down the birth canal, and the head appears.
  • Birth of the baby
    • Near the end of Stage 2, the shoulders emerge, followed quickly by the rest of the baby’s body.

The Baby’s Adaptation
to Labor and Delivery

• High levels of stress hormones
  • help baby withstand oxygen deprivation
  • prepare babyto breathe
  • arouse infant into alertness

Natural, or Prepared, Childbirth

• Classes
• Relaxation and breathing techniques
• Labor coach: friend, relative, or trained doula

Birth Complications

• Anoxia (oxygen deprivation)
• Breech position

Medical Interventions
in Childbirth

• Fetal monitoring
• Labor and delivery medication
  • analgesics
  • anesthetics
• Cesarean delivery

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

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

Newborn Reflexes

• Rooting
• Sucking
• Moro
• Stepping

Infant States of Arousal

• Rapid-eye-movement (REM) sleep
• Non-rapid-eye-movement (NREM) sleep
• Drowsiness
• Quiet alertness
• Waking activity and crying

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

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

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

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

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

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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