1. Chapter 4 – Prenatal Development and Birth
The Developing Person Through the Life Span 8e by Kathleen Stassen Berger
Chapter 4 – Prenatal Development and Birth
PowerPoint Slides developed by
Martin Wolfger and Michael James
Ivy Tech Community College-Bloomington
Reviewed by Raquel Henry
Lone Star College, Kingwood

2. Prenatal Growth Three main periods of prenatal development
Germinal Period (1st two weeks after conception): rapid cell division and beginning of cell differentiation
Embryonic Period (3rd through 8th week): basic forms of all body structures develop
Fetal Period (9th week until birth): fetus grows in size and matures in functioning

3. The Germinal Period
Zygote begins duplication and division within hours of conception
Development of the placenta
Organ that surrounds the developing embryo
Sustains life via the umbilical chord
Implantation (about 10 days after conception)
Developing organism burrows into the placenta that lines the uterus

4. The Germinal Period

5. The Embryonic Period Embryo 3rd through the 8th week after conception
Begins when the primitive streak appears down the middle of the cell mass
Primitive streak becomes the neural tube and later the brain and spinal column
Eyes, ears, nose, and mouth form
Heart begins to pulsate
Extremities develop and webbed fingers and toes separate

6. The Embryonic Period

7. The Fetal Period Fetus 9th week after conception until birth
Genitals form and sex hormones cause differences brain organization
Cephalocaudal and proximodistal growth
Heartbeat detectable via stethoscope
Cortex is not fully mature at birth
Brain at birth is biggest part of baby
Term: ultrasound

8. The Fetal Period Age of viability
Age at which a preterm newborn may survive outside the womb with medical care
About 22 weeks after conception
Brain is able to regulate basic body functions
Chances of survival increase with each day after the 22-week mark

9. The Fetal Period

10. Birth
Fetal brain signals the release of hormones to trigger the mother’s uterine muscles
Labor begins
Average duration for first babies: 12 hours
Quicker labor for later babies
Apgar scale
Quick assessment of newborn’s heart rate, breathing, muscle tone, color, and reflexes
Completed twice (1 minute and 5 minutes after birth)
Score of 0, 1, or 2 in each category
Desired score: 7 (total) or above

11. A Normal, Uncomplicated Birth

12. Birth

13. Medical Assistance Cesarean Section (c-section) Surgical birth
Fetus can be removed quickly
Rates and reasons for c-sections vary
Lower rates in poorer countries
Higher rates in richer countries
1/3 of births in the United States
Less trauma for the newborn but slower recovery for the mother
Subsequent cesarean deliveries may be necessary

15. Newborn Survival
Infant mortality has decreased due to better medical care
1900: 5%
Today: <1 in 200
Childbirth has become safer for mothers
Death rate in poorest nations: 1 in 20 women
Excessive medical care also has disadvantages
Increase in unnecessary c-sections is associated with higher rate of low-birth weight babies

16. Traditional and Modern Birthing Practices
Home births
Hospital births
Doula
Woman who helps with labor, delivery, breast-feeding, and newborn care
May be related to lower rate of cesarean sections

17. Harmful Substances Teratogens Behavioral teratogens
Substances and conditions that can impair prenatal development and result in birth defects or even death
Not all teratogens can be avoided
Structural abnormalities are obvious at birth
Behavioral teratogens
Affect the child’s developing brain
Developmental retardation, hyperactivity, and learning disabilities
Effects do not become evident for months or years

18. Risk Analysis Knowing which risks are worth taking
How to minimize chance of harm
Teratology: science of risk analysis
Threshold effect: when a teratogen is harmless in small doses but becomes harmful at a certain level (threshold)

20. Applying the Research Fetal alcohol syndrome (FAS)
A cluster of birth defects including abnormal facial characteristics, slow physical growth, and retarded mental development
May occur in the child of a woman who drinks alcohol while pregnant

21. Low Birthweight Low birthweight (LBW) Very low birthweight (VLBW)
Less than 2,500 grams (5½ pounds) at birth
United States
Steady increase in LBW over the past 25 years
8% of newborns are seriously underweight
More susceptible to teratogens, higher birth risks, lower survival rate
Very low birthweight (VLBW)
Under 1,500 grams (3 pounds, 5 ounces) at birth
Extremely low birthweight (ELBW)
Under 1,000 grams (2 pounds, 3 ounces) at birth

22. Preterm or Slow Growing?
Birth that occurs at 35 or fewer weeks after conception
Usually associated with low birthweight
Small for gestational age (SGA)
Birthweight is significantly lower than expected, given the time since conception
Suggests impairment throughout prenatal development and serious problems

23. Complications During Birth
Cerebral palsy:
-damage to the brain’s motor centers
-speech and/or muscles are impaired
Anoxia:
-lack of oxygen
-over time can cause brain damage or
death

24. The Newborn Brazelton Neonatal Behavioral Assessment Scale (NBAS)
A test that measures responsiveness
records 46 behaviors, including 20 reflexes

25. Moving and Perceiving The Newborn
The first movements are not skills but reflexes, involuntary responses to a particular stimulus.

26. The Newborn Some reflexes aid survival breathing thrashing shivering
sucking
rooting
swallowing
spitting up

27. The Newborn Other reflexes signify normal functioning:
Babinski reflex. When feet are stroked, their toes fan upward.
Stepping reflex. When held upright with feet touching a flat surface, infants move their legs as if to walk.
Swimming reflex. When laid horizontally on their stomachs, infants stretch out their arms and legs.
Palmar grasping reflex. When something touches infants’ palms, they grip it tightly.
Moro reflex. When someone startles them, infants fling their arms outward and then bring them together on their chests, as if to hold on to something, while crying with wide-open eyes.

28. The Father’s Role Supportive father helps mother stay healthy
Father can decrease or increase mother’s stress (affects fetus)
Most fathers are helpful to their pregnant wives
Two way street: Pregnant mothers should support, involve, and encourage fathers

29. The Father’s Role
Couvade: symptoms of pregnancy and birth experienced by fathers
Parental alliance:
cooperation between a mother and a father based on their mutual commitment to their children
the parents support each other in their shared parental roles.

30. Postpartum Depression
Sadness and inadequacy felt by 8-15% of new mothers in the days and weeks after giving birth
Symptoms range from baby blues to postpartum psychosis
baby care feels burdensome and thoughts of mistreating the infant may exist
Paternal involvement can have beneficial effect
Some fathers are depressed themselves
Causes for Postpartum Depression vary

31. Bonding Parent-Infant Bond
The strong, loving connection that forms as parents hold, examine, and feed the newborn
Early skin-to-skin contact is not essential
Cross-fostering in monkeys
Newborns are removed from their mothers and raised by another female or male
Strong and beneficial relationship sometimes develops

32. Bonding Birth complications can have lingering impact on later life
Mothers and fathers should help with early caregiving if newborn must stay in the hospital
Kangaroo care
Child-care technique in which the mother of a LBW infant holds the baby between her breasts
Allows baby to hear mother’s heartbeat and feel her body heat
Research confirms beneficial effects