I.  Prenatal development

            A.  Conception

                        Midway through menstrual cycle ovum is released

                                    a.  egg usually disintegrates

                                    b.  if woman has intercourse 300 million sperm enter body

                                                i.    6-hour journey to fallopian tubes

                                                ii.    one sperm may enter the egg

                                                iii.   biochemical reaction keeps other sperm from entering egg

                                                iv.   conception has taken place

            B.  Prenatal Stages

                        1.  Lasts for about 266 days (9 months)

                                    a.  zygote to fetus – one cell to billions

                                    b.  prenatal development occurs in three stages

                                                i.    germinal period

                                                ii.    period of embryo

                                                iii.   period of fetus

                        2.  The germinal period

                                    a.  lasts about 2 weeks

                                    b.  zygote divides to form blastula

                                                i.    hollow ball of 150 cells

                                                ii.    size of head of pin

                                    c.  as many as 50% terminate  

                        3.  The embryonic period

                                    a.  lasts from the third to eighth week

                                    b.  organogenesis-- every major organ takes shape

                                    c.  blastocyst forms layers

                                                i.    amnion-- watertight membrane surrounding

                                                ii.    chorion-- membrane on outside of amnion containing villi that

                                                      attach to uterine lining

                                                iii.   placenta-- tissue fed by mother’s blood vessels

                                                iv.   umbilical cord-- connection between embryo and mother

                                                      through which nutrients and wastes are exchanged

                                                v.  placental barrier-- membrane through which molecules pass

                                                vi.   ectoderm, mesoderm, and endoderm layers

                                    d.  brain development apparent after three to four weeks

                                                i.    neural plate forms neural tube (bottom is spinal cord)

                                                ii.    top of tube forms into forebrain, midbrain, hindbrain

                                                iii.   spina bifida-- spinal cord fails to become fully enclosed

                                                iv.   anencephaly-- tube at top fails to close, main portion of brain

                                                      fails to develop

                                                v.   encephalocele-- brain protrudes from skull

                                    e.  organs (e.g., heart, eyes) take shape

                                    f.  arms and legs appear

                                    g.  sexual differentiation

                                                i.    about seventh to eighth prenatal week, sex genes impact

                                                      formation of testes or ovaries

                                                ii.    secretion of testosterone by male embryo stimulate male

                                                      system and inhibits female system

                                                iii.   absence of correct hormones negatively impacts development

                        4.  The fetal period

                                    a.  ninth prenatal week to birth

                                    b.  significant brain development

                                                i.    proliferation of neurons (250,000 per minute)

                                                ii.    significant development between 10 and 20 weeks

                                                iii.   increase in number of glial cells

                                                iv.   neurons migrate into position

                                                v.  neurons begin to differentiate in function

                                                vi.   early cells known as stem cells

                                    c.  sex and sensory organs, bones, muscles, body systems

                                    d.  second trimester (months 4-6)

                                                i.   refined activities

                                                ii.    sensory organ development

                                    e.  age of viability-- around 24-25 weeks after conception has possibility

                                         of surviving outside uterus

                                    f.  third trimester (months 6-9)

                                                i.    rapid growth in length and weight

                                                ii.    brain development-- myelination

                                                iii.   infant states-- organization of behavior in waking and sleeping                                                                      patterns

                                                iv.   beginning of continuity between prenatal and postnatal


                                                v.  contractions of uterus typically begin birth process


II.  The prenatal environment

            Mother’s womb is environment for unborn child

            1940’s belief that placenta protected embryo and fetus from hazards

            New focus on environmental factors that negatively impact prenatal development

            A.  Teratogens

                        1.  Teratogens-- disease, drug, or environmental agent that can harm prenatal


                                    generalizations concerning teratogens

                                                i.    effects are worst during critical period when organs are forming

                                                ii.    effects determined by dosage and duration of exposure

                                                iii.   susceptibility is influenced by genetic makeup of mother and

                                                      fetus, and the quality of the prenatal environment

                                                iv.   prenatal and postnatal environments determine impact         

                                                v.  critical periods-- times when organism is highly sensitive to

                                                      damage (also called sensitive periods)

                        2.  Drugs

                                    a.  thalidomide

                                                i.    used in 1950s for relief of morning sickness

                                                ii.    major impact (e.g., flipper limbs, deformed ears, missing thumbs) if taken between 20 and 35 days

                                                iii.   banned but now being used to treat other disorders (e.g., cancer)

                                    b.  tobacco

                                                i.    despite warnings about 15% of pregnant women smoke

                                                ii.    inhibits prenatal growth, increases risk of miscarriage, retard

                                                      grow of fetus

                                                iii.   passive smoke also harmful

                                                iv.   increases odds of sudden infant death syndrome

                                    c.  alcohol

                                                i.    fetal alcohol syndrome-- cluster of symptoms (e.g., small size,

                                                      distinct facial features) associated with alcohol consumption

                                                      by pregnant women

                                                ii.    increased risk for hyperactivity, seizures, mental retardation,

                                                      attention deficit

                                                iii.   30% of pregnant women drink

                                                iv.   binge drinking and continuous patterns both can have negative


                                                v.  genetic and environmental factors (e.g., smoking, malnutrition)

                                                      may mediate impact

                                    d.  cocaine

                                                i.    damage includes spontaneous abortion, sensory skill deficits,

                                                      respiratory difficulty

                                                ii.    parental behaviors may also contribute to impact of cocaine

                        3.  Diseases

                                    a.  rubella-- German measles

                                                i.    impact:  blindness, deafness, heart defects, and retardation

                                                ii.    impact greatest during first trimester

                                                iii.   immunizations critical

                                    b.  syphilis

                                                i.    sexually transmitted

                                                ii.    impact includes blindness, deafness, heart defects, and


                                                iii.   impact greatest late in pregnancy-- cannot cross placental

                                                      barrier until 18th week

                                    c.  AIDS-- acquired immune deficiency disorder

                                                i.    caused by HIV

                                                ii.    destroys immune system

                                                iii.   transmitted prenatally, perinatally, postnatally (breastfeeding)

                                                iv.   mother-to-child transmission in U.S. decreased 40% since 1992


            4.  Environmental hazards

                                    a.  radiation

                                                i.    leads to mutation

                                                ii.    take care with X-ray

                                    b.  pollutants

                                                i.    heavy metals (e.g., lead) (e.g., lead) can have prenatal impact

                                                ii.    chemistry of prenatal environment can have major impact on


            B.  The Mother's State

                        1.  Age

                                    a.  ages 16-35 are "safest" childbearing years

                                    b.  younger risk due to immature reproductive system and poor medical


                                    c.  older risk due to miscarriage for often unknown reasons

                        2.  Emotional condition

                                    a.  prolonged, severe emotional stress may be damaging

                                    b.  damage may be due to stress hormones

                                    c.  presence of stress not as important as reaction to stress

                                    d.  anxiety and depression may also have impact

                        3.  Nutritional condition

                                    a.  recommend 25 to 35 pound weight gain (normal weight women)

                                    b.  malnutrition can lead to birth defects

                                                i.    first trimester malnutrition impact brain and spinal cord

                                                ii.    third trimester impact is smaller neurons, brain, and child

                                    c.  prenatal malnutrition impact may lead to predisposition to adult


                                    d.  adequate levels of folic acid important

            C.  The Father’s State

                        Little research on father’s contribution (beyond genetic)

                                    paternal age (over 40) may be risk factor

                                                i.    risk of Down syndrome higher for older men

                                                ii.    exposure to environmental toxin also increases risk             


III.  The perinatal environment

            Perinatal environment-- social and medical environment surrounding birth

            Birth has become more medicalized

            Use of supports like partners or doulas is on the rise

                        Presence of supports leads to more positive birthing experience

            A.  Birth is Three-Stage Process

                        1.  Contractions of uterus and dilation of cervix

                                    a.  duration average of 6 to 7 hours

                                    b.  ends with dilation of cervix of 10 centimeters

                        2.  Delivery of baby

                                    a.  fetus passes out of uterus

                                    b.  fetus emerges from woman’s body via the vaginal opening

                        3.  Delivery of placenta

                        4.  Participants often exhausted

            B.  Possible Hazards

                        1.  Anoxia-- oxygen shortage (also called asphyxia)                  

                                    a.  umbilical cord pinched or tangled

                                    b.  mucus in baby’s throat

                                    c.  sedatives given to mother

                                    d.  can cause mental retardation

                                    e.  can cause cerebral palsy-- neurological disability inhibiting movement

                                    f.  brief periods of anoxia typically harmless

                                    g.  breech position (feet or buttocks first) increases risk of anoxia

                                                i.    may prohibit vaginal delivery

                                                ii.    may lead to cesarean section-- surgical removal of baby

                        2.  Complicated delivery

                                    a.  forceps-- salad tong-like instrument used to help extract baby

                                    b.  vacuum extraction-- “suction-cup” device used to help extract baby

                                    c.  cesarean section (C-section) controversial but process is safe

                                                i.    account for 26% of U.S. births

                                                ii.    used to protect physician against malpractice suits

                                                iii.   planned C-section better than unplanned

                                                iv.   more revenue (expensive) than vaginal delivery

                                                v.   controversial case of mother being forced to use C-section

                        3.  Medications

                                    a.  sedatives can affect baby

                                    b.  regional analgesics (epidural or spinal block) deaden pain in area of

                                         body and have less affect on baby

            C.  The Mother’s Experience

                        1.  Psychological factors

                                    attitude, knowledge, sense of control, support impact experience

                        2.  Cultural factors

                                    a.  desirability to have children varies by culture

                                                China “one-child” policy

                                    b.  birth practices differ by culture

                                                Kenyan families celebrate, dad stops hunting, baby given ash and

                                                herbs to vomit amniotic fluid, mom given time to recover

                                    c.  Northern Indian childbirth seen as polluting and treated as shameful act

                                         (due to blood)

                                                i.    poorly trained and hateful dai helps deliver baby

                                                ii.    baby’s hair is shaved off

                                    d.  Western societies have “medicalized” childbirth and infant mortality

                                         rates have dropped morality rates significantly higher for black infants

                        3.  Postpartum depression

                                    a.  baby blues-- feelings of anxiety, irritability, and depression common for

                                         a few days after birth but typically fades

                                    b.  postpartum depression-- more serious post-birth feelings of anxiety,

                                         moodiness, and depression experienced by some women in months

                                         after birthing

                                    c.  postnatal depression rare but serious (tends to be found in women with

                                         history of depression or who few social supports

                                    d.  most women recover from postnatal depression but it may continue to

                                         influence mother-child interactions

                                    e.  children of postnatally depressed mothers may exhibit behavioral

                                         problems (e.g., violence) during late childhood and adolescence

                                    f.  professional help may be needed to overcome depression

            D.  The Father’s Experience

                        1.  Western society fathers historically excluded from birth process

                        2.  Impact both positive and negative


IV.  The neonatal environment

            Neonatal environment-- emphasis on newborn time of life

                        1.  Cross-cultural variation in beliefs concerning newborns

                                    a.  The Bengs view newborn as not of this world until after umbilical cord

                                         falls off (achieve full inhabitance around age 4-5 years)

                                    b.  The !Kung carry infant in slings and are indulged well into life

                                         breast-fed until age 4 years

                                    c.  Myan mothers sleep in bed with infant until they are toddlers

                        2.  Brazelton Neonatal Behavioral Assessment-- newborn assessment scale

                                    a.  assess reflexes and responses to 26 situations

                                    b.  test used to teach parents how to be responsive to infants

            A.  Identifying High-Risk Newborns

                        1.  At-risk status may be due to genetic, prenatal hazards, or perinatal damage

            2.  Apgar test-- used to assess newborn status

                        a.  assesses factors of heart rate, color, muscle tone, respiration, and


                        b.  score of 0, 1 or 2 for each factor

                                    c.  Apgar score of 7-10 good, 6 to 5 ok, less than 4 not good

                        3.  Low birth weight babies

                                    a.  weigh less than 2,500 grams or 5 1/2 pounds at birth

                                    b.  some are full-term and some are preterm

                                    c.  great increase in risk of infant death

                                    d.  linked to socioeconomic status

                                                prevention programs target health condition associated with


                                    e.  smoking and maternal stress contribute to low-birth-weight

                                    f.  associated with multiple births

                                                i.    increase in multiple births in part due to greater use of


                                                      stimulating drugs

                                                ii.    higher-order multiple births (3 or more children) have increased dramatically in past decades

                                    g.  with neonatal care many low-weight babies survive

                                    h.  surfactant-- substance that prevents air sacs in lungs from sticking

                                         together and allows for breathing

                                    i.  cerebral palsy more common neurological problem for low-birth-weight


                                    j.  fate of low-birth-weight infants depends on biological condition and

                                        parental responsiveness

                                    k.  intervention programs like Infant Health and Development Program

                                         benefit low-birth-weight infants

                                                i.    emphasis on growth-enhancing home environment

                                                ii.    linked to increased IQ score in childhood

                                    l.  responsive parenting critical

            B.  Risk and Resilience

                        1.  Werner and Smith longitudinal study of Hawaiian infants

                                    a.  children classified into risk groups

                                    b.  resilience-- ability to get back on course of normal development

                                                i.    effects of prenatal and perinatal complications decrease over


                                                ii.    quality of postnatal environment determines outcome of early


                        2.  Protective factors-- factors that help children overcome disadvantage

                                    a.  personal resources-- intellectual, sociability, and communication  traits

                                         that help one cope

                                    b.  supportive postnatal environment-- social support from environment

                                                environment matters throughout life