4.1
...
Infertility
not being able to get pregnant after a year of trying�is equally likely to be traced to the man as the woman and stems from a variety of causes
artificial insemination
(also called intrauterine insemination), which involves injecting sperm, either from a woman's partner or from a donor, into her uterus.
in vitro fertilization (IVF)
in which several eggs are removed from a woman's ovary and manually combined with sperm in a laboratory dish before being returned to a woman's uterus in hopes that one egg will implant on the wall of the uterus.
embryologists
who study early growth and development divide prenatal development into three stages or periods: the germinal period, the embryonic period, and the fetal period.
germinal period
which lasts approximately 2 weeks;
blastocyst
a hollow ball of about cells that is the size of the head of a pin
miscarriage
(also called spontaneous abortion)
embryonic period
which occurs from the third to the eighth week after conception
organogenesis
the process, occurring during the period of the embryo, in which major organs take shape.
amnion
a watertight membrane that fills with fluid that cushions and protects the embryo
Chorion
a membrane that surrounds the amnion and attaches rootlike extensions called villi to the uterine lining to gather nourishment for the embryo
placenta
a tissue fed by blood vessels from the mother and connected to the embryo by the umbilical cord
spina bifida
in which part of the spinal cord is not fully encased in the protective covering of the spinal column
anencephaly
a lethal defect in which the main portion of the brain above the brain stem fails to develop
testosterone
the primary male sex hormone that stimulates the development of a male internal reproductive system,
fetal period
lasts from the ninth week of pregnancy until birth, which means it encompasses part of the first trimester and all of the middle and last trimesters
Proliferation
Proliferation of neurons involves their multiplying at a staggering rate during this period; by one estimate, the number of neurons increases by hundreds of thousands every minute throughout all of pregnancy
migration
the neurons move from their place of origin in the center of the brain to particular locations throughout the brain where they will become part of specialized functioning units.
differentiation
In brain development, the progressive diversification of cells that results in their taking on different characteristics and functions.
age of viability
when survival outside the uterus is possible if the brain and respiratory system are sufficiently developed.
myelin
A fatty sheath that insulates neural axons and thereby speeds the transmission of neural impulses.
What is conception, and what techniques can be used to assist conception?
Conception occurs when a single sperm penetrates an ovum (or egg cell), quickly creating a zygote containing the 46 chromosomes that are the blueprint for that individual's life. There are several Assisted Reproductive Technologies (ARTs) that are used to
How does the development of the brain and nervous system unfold during the embryonic and fetal periods?
The brain and nervous system undergo dramatic change during the embryonic and fetal periods. From the interior of the primitive blastocyst, the ectoderm layer of cells gives rise to the brain and nervous system. The ectoderm folds into the neural tube and
When is survival outside the womb possible
The age of viability is reached at around 23-24 weeks of gestation and is influenced by many factors. Those infants surviving such early arrivals may experience serious health complications.
Based on what you know about the developments during the prenatal period, where would you focus attempts to optimize prenatal care and why?
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What ethical concerns should be considered with the use of artificial reproductive technologies? As technologies become more advanced in the future, what additional concerns may arise?
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4.2
...
fetal programming
brought about by such epigenetic effects of the environment
teratogen
is any disease, drug, or other environmental agent that can harm a developing fetus (for example, by causing deformities, blindness, brain damage, or even death).
critical period for an organ system
a time during which the developing organism is especially sensitive to environmental influences, positive or negative.
thalidomide
A mild tranquilizer that, taken early in pregnancy, can produce a variety of malformations of the limbs, eyes, ears, and heart.
sudden infant death syndrome (SIDS)
in which a sleeping baby suddenly stops breathing and dies
fetal alcohol syndrome (FAS)
A group of symptoms commonly observed in the offspring of mothers who use alcohol heavily during pregnancy, including a small head, widely spaced eyes, and mental retardation
rubella (German measles)
during pregnancy had one or more of a variety of defects, including blindness, deafness, heart defects, and intellectual disability
syphilis
A common sexually transmitted disease that may cross the placental barrier in the middle and later stages of pregnancy, causing miscarriage or serious birth defects.
acquired immunodeficiency syndrome (AIDS)
The life-threatening disease in which the human immunodeficiency virus (HIV) destroys the immune system and makes victims susceptible to rare, so-called opportunistic, infections that eventually kill them. AIDS is transmitted through sexual activity, drug
Lamaze method
of prepared childbirth teaches women to associate childbirth with pleasant feelings and to ready themselves for the process by learning exercises, breathing and pushing methods, and relaxation techniques that make childbirth easier
stillbirths
fetal deaths late in pregnancy
Most teratogens have their most devastating effects during the third trimester.
F the most serious problems occur during the first trimester when most major organs are forming
Women should monitor their fish consumption during pregnancy.
T (Some fish, such as swordfish, can contain high levels of the heavy metal mercury and should be avoided or eaten in small quantities.)
The fetus is protected from most environmental insults once it has fully implanted in the uterus and the umbilical cord has been completely established
umbilical cord is not a very good filter for many harmful substances. Carbon monoxide from cigarette smoke, for example, is actually "allowed" to cross the placenta before oxygen.)
Women who drink alcohol at any time during pregnancy will give birth to a baby with fetal alcohol syndrome.
F (Although FAS is a possibility, there are many variables that determine how an individual child will fare if exposed prenatally to alcohol. Certainly, the dosage generalization is important here: The more alcohol a woman drinks during pregnancy, the mor
A woman's age and race/ethnicity affect the odds of a healthy pregnancy.
T (Women between the ages of 20 and 35 have the lowest rates of fetal mortality. Non-Hispanic black women have some of the highest rates of fetal mortality and premature labor.)
What principles can help us understand the effects of teratogens?
Teratogens have their greatest impact during the critical period when an organ is emerging or rapidly developing; the effects depend on how much and for how long the fetus is exposed; the genetic makeup of both the unborn baby and the mother influence sus
What have researchers learned about the effects on the child of alcohol consumption during pregnancy?
Alcohol consumption during pregnancy, particularly if heavy and/or prolonged, can lead to fetal alcohol syndrome, a collection of physical and neurological problems with lifelong effects. Problems among children whose mothers drank during pregnancy includ
What effects are likely to be seen among babies born to mothers who smoked throughout their pregnancies?
Babies born to mothers who smoked throughout their pregnancies are more likely to be born premature and with low birth weight. They may experience respiratory problems as infants and behavioral problems as children. Some research shows that they are at gr
A close friend of yours has just gotten a positive reading on a home pregnancy test. What information would you give her about her activities during pregnancy and the potential impact of these on the development and health of her child?
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Consider Serena, whose story was summarized at the start of the chapter. What disadvantages might her child face, given Serena's lack of awareness of her pregnancy for the first 4-5 months?
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4.3
...
perinatal environment
is the environment surrounding birth; it includes influences such as drugs given to the mother during labor, delivery practices, and the social environment shortly after birth
perinatologist
A maternal-fetal specialist who focuses on high-risk pregnancies.
anoxia, or oxygen shortage (also called asphyxia).
can occur for any number of reasons�for example, because the umbilical cord becomes pinched or tangled during birth, because sedatives given to the mother reach the fetus and interfere with the baby's breathing,
breech presentation
(feet or buttocks first)
cerebral palsy
a neurological disability primarily associated with difficulty controlling muscle movements;
Cesarean section
a surgical procedure in which an incision is made in the mother's abdomen and uterus so that the baby can be removed.
oxytocin (brand name Pitocin)
a hormone released by the pituitary gland that can initiate and speed up contractions�moving labor along more quickly.
postpartum depression
an episode of clinical depression lasting 2 or more weeks (rather than days) in a woman who has just given birth
couvade
(from the French word meaning "to hatch"), include bloating, weight gain, fatigue, insomnia, and nausea
Sympathetic pregnancy, or the experiencing by fathers of some of the same physiological symptoms their pregnant partners experience (for example, bloat
What steps occur during the process of childbirth?
Childbirth begins with regular contractions of the uterus that eventually cause the woman's cervix to dilate or widen so the baby's head can pass through. The second stage of childbirth is the actual delivery of the baby from the mother's body, and the fi
What risks does the baby potentially face during the birth process
The birth process may pose risks for the baby if the flow of oxygen is cut off or if the baby is not in the head-down position that facilitates delivery. A prolonged labor can stress the unborn baby and lead to a cesarean section delivery. Some medication
Considering the research on birth and the perinatal environment, arrange the perfect birth experience for you and your baby and justify its features. Where would you be, who would be with you, and what would be done?
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Some experts worry that cesarean sections are overused. What do you think? Should a woman be able to choose whether she delivers vaginally or by cesarean section? Should hospitals be permitted to force a woman to deliver by cesarean if they believe the fe
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4.4
...
neonatal environment
the events of the first month and how parents might optimize the development of young infants.
at risk
Children who have a higher than normal chance of either short-term or long-term problems because of genetic defects, prenatal hazards, or perinatal damage.
Apgar test
A test routinely used to assess a newborn's heart rate, respiration, color, muscle tone, and reflexes immediately after birth and 5 minutes later; used to identify high-risk babies.
low birth weight (LBW)
A weight at birth of less than 2500 grams, or 5 � pounds, associated with increased risk of developmental problems.
surfactant
A substance that aids breathing by preventing the air sacs of the lungs from sticking together.
kangaroo care
resting on a parent's chest helps maintain body temperature, heart rate, and oxygen levels in the blood
resilience
The ability to function well despite exposure to risk factors for maladaptive development or to overcome early developmental problems to become well adjusted.
protective factors
Influences that prevent the damaging effects of risk factors or help children overcome disadvantages.
What are two things you can do during your baby's first weeks and months of life to ensure a healthy start to life?
Two important actions to ensure a good start to life include breastfeeding and identifying newborns who might be at risk for problems.
What are two factors that allow some babies to show resilience to negative events of the prenatal or perinatal periods?
Some babies seem to have more personal resources, such as "good genes" for traits that allow them to surmount difficulties. In addition, at-risk infants who grow up in a supportive postnatal environment are more likely to overcome negative events of the p
Find out if your mother and grandmothers breast-fed their children, including you, and for how long. What are your thoughts on the breast-versus-bottle choice? What factors might make it more or less likely that you or your partner will breast-feed (or ha
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Given the high costs of low birth weight, what programs would you make part of a national effort to reduce the number of LBW babies born each year?
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Practice Questions
...
A couple is not able to conceive a child naturally and choose a method where sperm is injected into the woman's uterus. What method is this couple trying?
a. artificial insemination
b. follicular fertilization
c. in vitro fertilization
d. infertility fert
artificial insemination
What is the fertilized egg called at the time of conception?
a. zygote
b. blastocyst
c. embryo
d. fetus
zygote
What structure develops from the chorion during the embryonic period?
a. villi
b. amnion
c. placenta
d. umbilical cord
Placenta
Neural tube defects tend to occur during which part of prenatal development?
a. the first three months
b. months three through six
c. at any time during pregnancy
d. the first month
the first month
Rita is pregnant. At about how many weeks after conception can her fetus be considered to have reached the age of viability?
a. 13 weeks
b. 23 weeks
c. 26 weeks
d. 17 weeks
23 weeks
If an embryo is exposed to a teratogen at five weeks gestation, what organ or body part is most likely to be affected?
a. ears
b. lungs
c. facial features
d. arms
arms
What is the critical period for development of the heart?
a. 4-7 weeks gestation
b. 3-6 weeks gestation
c. 6-8 weeks gestation
d. 3-12 weeks gestation
3-6 weeks gestation
What percentage of infants born to mothers who smoke 20 or more cigarettes a day end up in neonatal intensive care?
a. 10%
b. 40%
c. 20%
d. 50%
50%
How many babies born in the United States have Fetal Alcohol Syndrome?
a. 3 in 100,000
b. 3 in 100
c. 3 in 10,000
d. 3 in 1000
3 in 1000
Which of the following can be caused by both prenatal and postnatal exposure to lead?
a. stunted growth
b. respiratory problems
c. impaired intellectual functioning
d. facial abnormalities
impaired intellectual functioning
Edna has been depressed for much of her pregnancy. How is this likely to affect her newborn?
a. heart defects
b. delays in motor skills
c. impaired cognitive functioning
d. stunted prenatal growth
delays in motor skills
Norma is a normal-weight woman. What would be considered to be a healthy weight gain for her during her pregnancy?
a. 10 to 15 pounds
b. 25 to 35 pounds
c. 15 to 20 pounds
d. 40 to 50 pounds
25 to 35 pounds
Fred, age 55, is planning to have a baby with his wife. Due to Fred's advanced age, his child will be at an increased risk for ________ .
a. substance abuse
b. anxiety
c. depression
d. schizophrenia
schizophrenia
The first stage of childbirth ends when the cervix has dilated to ________ centimeters.
a. 7
b. 13
c. 4
d. 10
10
Anna's birth was assisted by a suction cup that was adhered to her scalp. What is this procedure called?
a. forceps
b. epidural
c. vacuum extraction
d. cesarean-section
vacuum extraction
What drug is sometimes given during labor to induce or intensify uterine contractions?
a. oxytocin
b. sedative
c. anesthetic
d. epidural
oxytocin
What percentage of women experience postpartum depression following childbirth?
a. 40 percent
b. 1 percent
c. 15 percent
d. 25 percent
15%
A score of ________ or lower on the Apgar test indicates that a newborn is at-risk.
a. 7
b. 10
c. 1
d. 4
4
Tony is a premature infant. What type of therapy might he be given to aid his breathing?
a. surfactant
b. hypothermia
c. oxytocin
d. light therapy
surfactant
Longitudinal studies of risk and resilience have found that, among individuals judged to be at risk based on prenatal and perinatal stress, ________ .
a. about one-third show resilience and develop into competent and successful adults
b. about half show r
about one-third show resilience and develop into competent and successful adults